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1 /* $OpenBSD: ssh-keyscan.c,v 1.99 2015/01/30 10:44:49 djm Exp $ */
2 /*
3  * Copyright 1995, 1996 by David Mazieres <dm@lcs.mit.edu>.
4  *
5  * Modification and redistribution in source and binary forms is
6  * permitted provided that due credit is given to the author and the
7  * OpenBSD project by leaving this copyright notice intact.
8  */
9 
10 #include "includes.h"
11 
12 #include <sys/types.h>
13 #include "openbsd-compat/sys-queue.h"
14 #include <sys/resource.h>
15 #ifdef HAVE_SYS_TIME_H
16 # include <sys/time.h>
17 #endif
18 
19 #include <netinet/in.h>
20 #include <arpa/inet.h>
21 
22 #include <openssl/bn.h>
23 
24 #include <netdb.h>
25 #include <errno.h>
26 #include <stdarg.h>
27 #include <stdio.h>
28 #include <stdlib.h>
29 #include <signal.h>
30 #include <string.h>
31 #include <unistd.h>
32 
33 #include "xmalloc.h"
34 #include "ssh.h"
35 #include "ssh1.h"
36 #include "sshbuf.h"
37 #include "sshkey.h"
38 #include "cipher.h"
39 #include "kex.h"
40 #include "compat.h"
41 #include "myproposal.h"
42 #include "packet.h"
43 #include "dispatch.h"
44 #include "log.h"
45 #include "atomicio.h"
46 #include "misc.h"
47 #include "hostfile.h"
48 #include "ssherr.h"
49 #include "ssh_api.h"
50 
51 /* Flag indicating whether IPv4 or IPv6.  This can be set on the command line.
52    Default value is AF_UNSPEC means both IPv4 and IPv6. */
53 int IPv4or6 = AF_UNSPEC;
54 
55 int ssh_port = SSH_DEFAULT_PORT;
56 
57 #define KT_RSA1		1
58 #define KT_DSA		2
59 #define KT_RSA		4
60 #define KT_ECDSA	8
61 #define KT_ED25519	16
62 
63 int get_keytypes = KT_RSA|KT_ECDSA|KT_ED25519;
64 
65 int hash_hosts = 0;		/* Hash hostname on output */
66 
67 #define MAXMAXFD 256
68 
69 /* The number of seconds after which to give up on a TCP connection */
70 int timeout = 5;
71 
72 int maxfd;
73 #define MAXCON (maxfd - 10)
74 
75 extern char *__progname;
76 fd_set *read_wait;
77 size_t read_wait_nfdset;
78 int ncon;
79 
80 struct ssh *active_state = NULL; /* XXX needed for linking */
81 
82 /*
83  * Keep a connection structure for each file descriptor.  The state
84  * associated with file descriptor n is held in fdcon[n].
85  */
86 typedef struct Connection {
87 	u_char c_status;	/* State of connection on this file desc. */
88 #define CS_UNUSED 0		/* File descriptor unused */
89 #define CS_CON 1		/* Waiting to connect/read greeting */
90 #define CS_SIZE 2		/* Waiting to read initial packet size */
91 #define CS_KEYS 3		/* Waiting to read public key packet */
92 	int c_fd;		/* Quick lookup: c->c_fd == c - fdcon */
93 	int c_plen;		/* Packet length field for ssh packet */
94 	int c_len;		/* Total bytes which must be read. */
95 	int c_off;		/* Length of data read so far. */
96 	int c_keytype;		/* Only one of KT_RSA1, KT_DSA, or KT_RSA */
97 	int c_done;		/* SSH2 done */
98 	char *c_namebase;	/* Address to free for c_name and c_namelist */
99 	char *c_name;		/* Hostname of connection for errors */
100 	char *c_namelist;	/* Pointer to other possible addresses */
101 	char *c_output_name;	/* Hostname of connection for output */
102 	char *c_data;		/* Data read from this fd */
103 	struct ssh *c_ssh;	/* SSH-connection */
104 	struct timeval c_tv;	/* Time at which connection gets aborted */
105 	TAILQ_ENTRY(Connection) c_link;	/* List of connections in timeout order. */
106 } con;
107 
108 TAILQ_HEAD(conlist, Connection) tq;	/* Timeout Queue */
109 con *fdcon;
110 
111 static void keyprint(con *c, struct sshkey *key);
112 
113 static int
fdlim_get(int hard)114 fdlim_get(int hard)
115 {
116 #if defined(HAVE_GETRLIMIT) && defined(RLIMIT_NOFILE)
117 	struct rlimit rlfd;
118 
119 	if (getrlimit(RLIMIT_NOFILE, &rlfd) < 0)
120 		return (-1);
121 	if ((hard ? rlfd.rlim_max : rlfd.rlim_cur) == RLIM_INFINITY)
122 		return SSH_SYSFDMAX;
123 	else
124 		return hard ? rlfd.rlim_max : rlfd.rlim_cur;
125 #else
126 	return SSH_SYSFDMAX;
127 #endif
128 }
129 
130 static int
fdlim_set(int lim)131 fdlim_set(int lim)
132 {
133 #if defined(HAVE_SETRLIMIT) && defined(RLIMIT_NOFILE)
134 	struct rlimit rlfd;
135 #endif
136 
137 	if (lim <= 0)
138 		return (-1);
139 #if defined(HAVE_SETRLIMIT) && defined(RLIMIT_NOFILE)
140 	if (getrlimit(RLIMIT_NOFILE, &rlfd) < 0)
141 		return (-1);
142 	rlfd.rlim_cur = lim;
143 	if (setrlimit(RLIMIT_NOFILE, &rlfd) < 0)
144 		return (-1);
145 #elif defined (HAVE_SETDTABLESIZE)
146 	setdtablesize(lim);
147 #endif
148 	return (0);
149 }
150 
151 /*
152  * This is an strsep function that returns a null field for adjacent
153  * separators.  This is the same as the 4.4BSD strsep, but different from the
154  * one in the GNU libc.
155  */
156 static char *
xstrsep(char ** str,const char * delim)157 xstrsep(char **str, const char *delim)
158 {
159 	char *s, *e;
160 
161 	if (!**str)
162 		return (NULL);
163 
164 	s = *str;
165 	e = s + strcspn(s, delim);
166 
167 	if (*e != '\0')
168 		*e++ = '\0';
169 	*str = e;
170 
171 	return (s);
172 }
173 
174 /*
175  * Get the next non-null token (like GNU strsep).  Strsep() will return a
176  * null token for two adjacent separators, so we may have to loop.
177  */
178 static char *
strnnsep(char ** stringp,char * delim)179 strnnsep(char **stringp, char *delim)
180 {
181 	char *tok;
182 
183 	do {
184 		tok = xstrsep(stringp, delim);
185 	} while (tok && *tok == '\0');
186 	return (tok);
187 }
188 
189 #ifdef WITH_SSH1
190 static struct sshkey *
keygrab_ssh1(con * c)191 keygrab_ssh1(con *c)
192 {
193 	static struct sshkey *rsa;
194 	static struct sshbuf *msg;
195 	int r;
196 	u_char type;
197 
198 	if (rsa == NULL) {
199 		if ((rsa = sshkey_new(KEY_RSA1)) == NULL) {
200 			error("%s: sshkey_new failed", __func__);
201 			return NULL;
202 		}
203 		if ((msg = sshbuf_new()) == NULL)
204 			fatal("%s: sshbuf_new failed", __func__);
205 	}
206 	if ((r = sshbuf_put(msg, c->c_data, c->c_plen)) != 0 ||
207 	    (r = sshbuf_consume(msg, 8 - (c->c_plen & 7))) != 0 || /* padding */
208 	    (r = sshbuf_get_u8(msg, &type)) != 0)
209 		goto buf_err;
210 	if (type != (int) SSH_SMSG_PUBLIC_KEY) {
211 		error("%s: invalid packet type", c->c_name);
212 		sshbuf_reset(msg);
213 		return NULL;
214 	}
215 	if ((r = sshbuf_consume(msg, 8)) != 0 || /* cookie */
216 	    /* server key */
217 	    (r = sshbuf_get_u32(msg, NULL)) != 0 ||
218 	    (r = sshbuf_get_bignum1(msg, NULL)) != 0 ||
219 	    (r = sshbuf_get_bignum1(msg, NULL)) != 0 ||
220 	    /* host key */
221 	    (r = sshbuf_get_u32(msg, NULL)) != 0 ||
222 	    (r = sshbuf_get_bignum1(msg, rsa->rsa->e)) != 0 ||
223 	    (r = sshbuf_get_bignum1(msg, rsa->rsa->n)) != 0) {
224  buf_err:
225 		error("%s: buffer error: %s", __func__, ssh_err(r));
226 		sshbuf_reset(msg);
227 		return NULL;
228 	}
229 
230 	sshbuf_reset(msg);
231 
232 	return (rsa);
233 }
234 #endif
235 
236 static int
key_print_wrapper(struct sshkey * hostkey,struct ssh * ssh)237 key_print_wrapper(struct sshkey *hostkey, struct ssh *ssh)
238 {
239 	con *c;
240 
241 	if ((c = ssh_get_app_data(ssh)) != NULL)
242 		keyprint(c, hostkey);
243 	/* always abort key exchange */
244 	return -1;
245 }
246 
247 static int
ssh2_capable(int remote_major,int remote_minor)248 ssh2_capable(int remote_major, int remote_minor)
249 {
250 	switch (remote_major) {
251 	case 1:
252 		if (remote_minor == 99)
253 			return 1;
254 		break;
255 	case 2:
256 		return 1;
257 	default:
258 		break;
259 	}
260 	return 0;
261 }
262 
263 static void
keygrab_ssh2(con * c)264 keygrab_ssh2(con *c)
265 {
266 	char *myproposal[PROPOSAL_MAX] = { KEX_CLIENT };
267 	int r;
268 
269 	enable_compat20();
270 	myproposal[PROPOSAL_SERVER_HOST_KEY_ALGS] =
271 	    c->c_keytype == KT_DSA ?  "ssh-dss" :
272 	    (c->c_keytype == KT_RSA ? "ssh-rsa" :
273 	    (c->c_keytype == KT_ED25519 ? "ssh-ed25519" :
274 	    "ecdsa-sha2-nistp256,ecdsa-sha2-nistp384,ecdsa-sha2-nistp521"));
275 	if ((r = kex_setup(c->c_ssh, myproposal)) != 0) {
276 		free(c->c_ssh);
277 		fprintf(stderr, "kex_setup: %s\n", ssh_err(r));
278 		exit(1);
279 	}
280 #ifdef WITH_OPENSSL
281 	c->c_ssh->kex->kex[KEX_DH_GRP1_SHA1] = kexdh_client;
282 	c->c_ssh->kex->kex[KEX_DH_GRP14_SHA1] = kexdh_client;
283 	c->c_ssh->kex->kex[KEX_DH_GEX_SHA1] = kexgex_client;
284 	c->c_ssh->kex->kex[KEX_DH_GEX_SHA256] = kexgex_client;
285 # ifdef OPENSSL_HAS_ECC
286 	c->c_ssh->kex->kex[KEX_ECDH_SHA2] = kexecdh_client;
287 # endif
288 #endif
289 	c->c_ssh->kex->kex[KEX_C25519_SHA256] = kexc25519_client;
290 	ssh_set_verify_host_key_callback(c->c_ssh, key_print_wrapper);
291 	/*
292 	 * do the key-exchange until an error occurs or until
293 	 * the key_print_wrapper() callback sets c_done.
294 	 */
295 	ssh_dispatch_run(c->c_ssh, DISPATCH_BLOCK, &c->c_done, c->c_ssh);
296 }
297 
298 static void
keyprint(con * c,struct sshkey * key)299 keyprint(con *c, struct sshkey *key)
300 {
301 	char *host = c->c_output_name ? c->c_output_name : c->c_name;
302 
303 	if (!key)
304 		return;
305 	if (hash_hosts && (host = host_hash(host, NULL, 0)) == NULL)
306 		fatal("host_hash failed");
307 
308 	fprintf(stdout, "%s ", host);
309 	sshkey_write(key, stdout);
310 	fputs("\n", stdout);
311 }
312 
313 static int
tcpconnect(char * host)314 tcpconnect(char *host)
315 {
316 	struct addrinfo hints, *ai, *aitop;
317 	char strport[NI_MAXSERV];
318 	int gaierr, s = -1;
319 
320 	snprintf(strport, sizeof strport, "%d", ssh_port);
321 	memset(&hints, 0, sizeof(hints));
322 	hints.ai_family = IPv4or6;
323 	hints.ai_socktype = SOCK_STREAM;
324 	if ((gaierr = getaddrinfo(host, strport, &hints, &aitop)) != 0) {
325 		error("getaddrinfo %s: %s", host, ssh_gai_strerror(gaierr));
326 		return -1;
327 	}
328 	for (ai = aitop; ai; ai = ai->ai_next) {
329 		s = socket(ai->ai_family, ai->ai_socktype, ai->ai_protocol);
330 		if (s < 0) {
331 			error("socket: %s", strerror(errno));
332 			continue;
333 		}
334 		if (set_nonblock(s) == -1)
335 			fatal("%s: set_nonblock(%d)", __func__, s);
336 		if (connect(s, ai->ai_addr, ai->ai_addrlen) < 0 &&
337 		    errno != EINPROGRESS)
338 			error("connect (`%s'): %s", host, strerror(errno));
339 		else
340 			break;
341 		close(s);
342 		s = -1;
343 	}
344 	freeaddrinfo(aitop);
345 	return s;
346 }
347 
348 static int
conalloc(char * iname,char * oname,int keytype)349 conalloc(char *iname, char *oname, int keytype)
350 {
351 	char *namebase, *name, *namelist;
352 	int s;
353 
354 	namebase = namelist = xstrdup(iname);
355 
356 	do {
357 		name = xstrsep(&namelist, ",");
358 		if (!name) {
359 			free(namebase);
360 			return (-1);
361 		}
362 	} while ((s = tcpconnect(name)) < 0);
363 
364 	if (s >= maxfd)
365 		fatal("conalloc: fdno %d too high", s);
366 	if (fdcon[s].c_status)
367 		fatal("conalloc: attempt to reuse fdno %d", s);
368 
369 	fdcon[s].c_fd = s;
370 	fdcon[s].c_status = CS_CON;
371 	fdcon[s].c_namebase = namebase;
372 	fdcon[s].c_name = name;
373 	fdcon[s].c_namelist = namelist;
374 	fdcon[s].c_output_name = xstrdup(oname);
375 	fdcon[s].c_data = (char *) &fdcon[s].c_plen;
376 	fdcon[s].c_len = 4;
377 	fdcon[s].c_off = 0;
378 	fdcon[s].c_keytype = keytype;
379 	gettimeofday(&fdcon[s].c_tv, NULL);
380 	fdcon[s].c_tv.tv_sec += timeout;
381 	TAILQ_INSERT_TAIL(&tq, &fdcon[s], c_link);
382 	FD_SET(s, read_wait);
383 	ncon++;
384 	return (s);
385 }
386 
387 static void
confree(int s)388 confree(int s)
389 {
390 	if (s >= maxfd || fdcon[s].c_status == CS_UNUSED)
391 		fatal("confree: attempt to free bad fdno %d", s);
392 	close(s);
393 	free(fdcon[s].c_namebase);
394 	free(fdcon[s].c_output_name);
395 	if (fdcon[s].c_status == CS_KEYS)
396 		free(fdcon[s].c_data);
397 	fdcon[s].c_status = CS_UNUSED;
398 	fdcon[s].c_keytype = 0;
399 	if (fdcon[s].c_ssh) {
400 		ssh_packet_close(fdcon[s].c_ssh);
401 		free(fdcon[s].c_ssh);
402 		fdcon[s].c_ssh = NULL;
403 	}
404 	TAILQ_REMOVE(&tq, &fdcon[s], c_link);
405 	FD_CLR(s, read_wait);
406 	ncon--;
407 }
408 
409 static void
contouch(int s)410 contouch(int s)
411 {
412 	TAILQ_REMOVE(&tq, &fdcon[s], c_link);
413 	gettimeofday(&fdcon[s].c_tv, NULL);
414 	fdcon[s].c_tv.tv_sec += timeout;
415 	TAILQ_INSERT_TAIL(&tq, &fdcon[s], c_link);
416 }
417 
418 static int
conrecycle(int s)419 conrecycle(int s)
420 {
421 	con *c = &fdcon[s];
422 	int ret;
423 
424 	ret = conalloc(c->c_namelist, c->c_output_name, c->c_keytype);
425 	confree(s);
426 	return (ret);
427 }
428 
429 static void
congreet(int s)430 congreet(int s)
431 {
432 	int n = 0, remote_major = 0, remote_minor = 0;
433 	char buf[256], *cp;
434 	char remote_version[sizeof buf];
435 	size_t bufsiz;
436 	con *c = &fdcon[s];
437 
438 	for (;;) {
439 		memset(buf, '\0', sizeof(buf));
440 		bufsiz = sizeof(buf);
441 		cp = buf;
442 		while (bufsiz-- &&
443 		    (n = atomicio(read, s, cp, 1)) == 1 && *cp != '\n') {
444 			if (*cp == '\r')
445 				*cp = '\n';
446 			cp++;
447 		}
448 		if (n != 1 || strncmp(buf, "SSH-", 4) == 0)
449 			break;
450 	}
451 	if (n == 0) {
452 		switch (errno) {
453 		case EPIPE:
454 			error("%s: Connection closed by remote host", c->c_name);
455 			break;
456 		case ECONNREFUSED:
457 			break;
458 		default:
459 			error("read (%s): %s", c->c_name, strerror(errno));
460 			break;
461 		}
462 		conrecycle(s);
463 		return;
464 	}
465 	if (*cp != '\n' && *cp != '\r') {
466 		error("%s: bad greeting", c->c_name);
467 		confree(s);
468 		return;
469 	}
470 	*cp = '\0';
471 	if ((c->c_ssh = ssh_packet_set_connection(NULL, s, s)) == NULL)
472 		fatal("ssh_packet_set_connection failed");
473 	ssh_packet_set_timeout(c->c_ssh, timeout, 1);
474 	ssh_set_app_data(c->c_ssh, c);	/* back link */
475 	if (sscanf(buf, "SSH-%d.%d-%[^\n]\n",
476 	    &remote_major, &remote_minor, remote_version) == 3)
477 		c->c_ssh->compat = compat_datafellows(remote_version);
478 	else
479 		c->c_ssh->compat = 0;
480 	if (c->c_keytype != KT_RSA1) {
481 		if (!ssh2_capable(remote_major, remote_minor)) {
482 			debug("%s doesn't support ssh2", c->c_name);
483 			confree(s);
484 			return;
485 		}
486 	} else if (remote_major != 1) {
487 		debug("%s doesn't support ssh1", c->c_name);
488 		confree(s);
489 		return;
490 	}
491 	fprintf(stderr, "# %s %s\n", c->c_name, chop(buf));
492 	n = snprintf(buf, sizeof buf, "SSH-%d.%d-OpenSSH-keyscan\r\n",
493 	    c->c_keytype == KT_RSA1? PROTOCOL_MAJOR_1 : PROTOCOL_MAJOR_2,
494 	    c->c_keytype == KT_RSA1? PROTOCOL_MINOR_1 : PROTOCOL_MINOR_2);
495 	if (n < 0 || (size_t)n >= sizeof(buf)) {
496 		error("snprintf: buffer too small");
497 		confree(s);
498 		return;
499 	}
500 	if (atomicio(vwrite, s, buf, n) != (size_t)n) {
501 		error("write (%s): %s", c->c_name, strerror(errno));
502 		confree(s);
503 		return;
504 	}
505 	if (c->c_keytype != KT_RSA1) {
506 		keygrab_ssh2(c);
507 		confree(s);
508 		return;
509 	}
510 	c->c_status = CS_SIZE;
511 	contouch(s);
512 }
513 
514 static void
conread(int s)515 conread(int s)
516 {
517 	con *c = &fdcon[s];
518 	size_t n;
519 
520 	if (c->c_status == CS_CON) {
521 		congreet(s);
522 		return;
523 	}
524 	n = atomicio(read, s, c->c_data + c->c_off, c->c_len - c->c_off);
525 	if (n == 0) {
526 		error("read (%s): %s", c->c_name, strerror(errno));
527 		confree(s);
528 		return;
529 	}
530 	c->c_off += n;
531 
532 	if (c->c_off == c->c_len)
533 		switch (c->c_status) {
534 		case CS_SIZE:
535 			c->c_plen = htonl(c->c_plen);
536 			c->c_len = c->c_plen + 8 - (c->c_plen & 7);
537 			c->c_off = 0;
538 			c->c_data = xmalloc(c->c_len);
539 			c->c_status = CS_KEYS;
540 			break;
541 #ifdef WITH_SSH1
542 		case CS_KEYS:
543 			keyprint(c, keygrab_ssh1(c));
544 			confree(s);
545 			return;
546 #endif
547 		default:
548 			fatal("conread: invalid status %d", c->c_status);
549 			break;
550 		}
551 
552 	contouch(s);
553 }
554 
555 static void
conloop(void)556 conloop(void)
557 {
558 	struct timeval seltime, now;
559 	fd_set *r, *e;
560 	con *c;
561 	int i;
562 
563 	gettimeofday(&now, NULL);
564 	c = TAILQ_FIRST(&tq);
565 
566 	if (c && (c->c_tv.tv_sec > now.tv_sec ||
567 	    (c->c_tv.tv_sec == now.tv_sec && c->c_tv.tv_usec > now.tv_usec))) {
568 		seltime = c->c_tv;
569 		seltime.tv_sec -= now.tv_sec;
570 		seltime.tv_usec -= now.tv_usec;
571 		if (seltime.tv_usec < 0) {
572 			seltime.tv_usec += 1000000;
573 			seltime.tv_sec--;
574 		}
575 	} else
576 		timerclear(&seltime);
577 
578 	r = xcalloc(read_wait_nfdset, sizeof(fd_mask));
579 	e = xcalloc(read_wait_nfdset, sizeof(fd_mask));
580 	memcpy(r, read_wait, read_wait_nfdset * sizeof(fd_mask));
581 	memcpy(e, read_wait, read_wait_nfdset * sizeof(fd_mask));
582 
583 	while (select(maxfd, r, NULL, e, &seltime) == -1 &&
584 	    (errno == EAGAIN || errno == EINTR || errno == EWOULDBLOCK))
585 		;
586 
587 	for (i = 0; i < maxfd; i++) {
588 		if (FD_ISSET(i, e)) {
589 			error("%s: exception!", fdcon[i].c_name);
590 			confree(i);
591 		} else if (FD_ISSET(i, r))
592 			conread(i);
593 	}
594 	free(r);
595 	free(e);
596 
597 	c = TAILQ_FIRST(&tq);
598 	while (c && (c->c_tv.tv_sec < now.tv_sec ||
599 	    (c->c_tv.tv_sec == now.tv_sec && c->c_tv.tv_usec < now.tv_usec))) {
600 		int s = c->c_fd;
601 
602 		c = TAILQ_NEXT(c, c_link);
603 		conrecycle(s);
604 	}
605 }
606 
607 static void
do_host(char * host)608 do_host(char *host)
609 {
610 	char *name = strnnsep(&host, " \t\n");
611 	int j;
612 
613 	if (name == NULL)
614 		return;
615 	for (j = KT_RSA1; j <= KT_ED25519; j *= 2) {
616 		if (get_keytypes & j) {
617 			while (ncon >= MAXCON)
618 				conloop();
619 			conalloc(name, *host ? host : name, j);
620 		}
621 	}
622 }
623 
624 void
fatal(const char * fmt,...)625 fatal(const char *fmt,...)
626 {
627 	va_list args;
628 
629 	va_start(args, fmt);
630 	do_log(SYSLOG_LEVEL_FATAL, fmt, args);
631 	va_end(args);
632 	exit(255);
633 }
634 
635 static void
usage(void)636 usage(void)
637 {
638 	fprintf(stderr,
639 	    "usage: %s [-46Hv] [-f file] [-p port] [-T timeout] [-t type]\n"
640 	    "\t\t   [host | addrlist namelist] ...\n",
641 	    __progname);
642 	exit(1);
643 }
644 
645 int
main(int argc,char ** argv)646 main(int argc, char **argv)
647 {
648 	int debug_flag = 0, log_level = SYSLOG_LEVEL_INFO;
649 	int opt, fopt_count = 0, j;
650 	char *tname, *cp, line[NI_MAXHOST];
651 	FILE *fp;
652 	u_long linenum;
653 
654 	extern int optind;
655 	extern char *optarg;
656 
657 	__progname = ssh_get_progname(argv[0]);
658 	seed_rng();
659 	TAILQ_INIT(&tq);
660 
661 	/* Ensure that fds 0, 1 and 2 are open or directed to /dev/null */
662 	sanitise_stdfd();
663 
664 	if (argc <= 1)
665 		usage();
666 
667 	while ((opt = getopt(argc, argv, "Hv46p:T:t:f:")) != -1) {
668 		switch (opt) {
669 		case 'H':
670 			hash_hosts = 1;
671 			break;
672 		case 'p':
673 			ssh_port = a2port(optarg);
674 			if (ssh_port <= 0) {
675 				fprintf(stderr, "Bad port '%s'\n", optarg);
676 				exit(1);
677 			}
678 			break;
679 		case 'T':
680 			timeout = convtime(optarg);
681 			if (timeout == -1 || timeout == 0) {
682 				fprintf(stderr, "Bad timeout '%s'\n", optarg);
683 				usage();
684 			}
685 			break;
686 		case 'v':
687 			if (!debug_flag) {
688 				debug_flag = 1;
689 				log_level = SYSLOG_LEVEL_DEBUG1;
690 			}
691 			else if (log_level < SYSLOG_LEVEL_DEBUG3)
692 				log_level++;
693 			else
694 				fatal("Too high debugging level.");
695 			break;
696 		case 'f':
697 			if (strcmp(optarg, "-") == 0)
698 				optarg = NULL;
699 			argv[fopt_count++] = optarg;
700 			break;
701 		case 't':
702 			get_keytypes = 0;
703 			tname = strtok(optarg, ",");
704 			while (tname) {
705 				int type = sshkey_type_from_name(tname);
706 				switch (type) {
707 				case KEY_RSA1:
708 					get_keytypes |= KT_RSA1;
709 					break;
710 				case KEY_DSA:
711 					get_keytypes |= KT_DSA;
712 					break;
713 				case KEY_ECDSA:
714 					get_keytypes |= KT_ECDSA;
715 					break;
716 				case KEY_RSA:
717 					get_keytypes |= KT_RSA;
718 					break;
719 				case KEY_ED25519:
720 					get_keytypes |= KT_ED25519;
721 					break;
722 				case KEY_UNSPEC:
723 					fatal("unknown key type %s", tname);
724 				}
725 				tname = strtok(NULL, ",");
726 			}
727 			break;
728 		case '4':
729 			IPv4or6 = AF_INET;
730 			break;
731 		case '6':
732 			IPv4or6 = AF_INET6;
733 			break;
734 		case '?':
735 		default:
736 			usage();
737 		}
738 	}
739 	if (optind == argc && !fopt_count)
740 		usage();
741 
742 	log_init("ssh-keyscan", log_level, SYSLOG_FACILITY_USER, 1);
743 
744 	maxfd = fdlim_get(1);
745 	if (maxfd < 0)
746 		fatal("%s: fdlim_get: bad value", __progname);
747 	if (maxfd > MAXMAXFD)
748 		maxfd = MAXMAXFD;
749 	if (MAXCON <= 0)
750 		fatal("%s: not enough file descriptors", __progname);
751 	if (maxfd > fdlim_get(0))
752 		fdlim_set(maxfd);
753 	fdcon = xcalloc(maxfd, sizeof(con));
754 
755 	read_wait_nfdset = howmany(maxfd, NFDBITS);
756 	read_wait = xcalloc(read_wait_nfdset, sizeof(fd_mask));
757 
758 	for (j = 0; j < fopt_count; j++) {
759 		if (argv[j] == NULL)
760 			fp = stdin;
761 		else if ((fp = fopen(argv[j], "r")) == NULL)
762 			fatal("%s: %s: %s", __progname, argv[j],
763 			    strerror(errno));
764 		linenum = 0;
765 
766 		while (read_keyfile_line(fp,
767 		    argv[j] == NULL ? "(stdin)" : argv[j], line, sizeof(line),
768 		    &linenum) != -1) {
769 			/* Chomp off trailing whitespace and comments */
770 			if ((cp = strchr(line, '#')) == NULL)
771 				cp = line + strlen(line) - 1;
772 			while (cp >= line) {
773 				if (*cp == ' ' || *cp == '\t' ||
774 				    *cp == '\n' || *cp == '#')
775 					*cp-- = '\0';
776 				else
777 					break;
778 			}
779 
780 			/* Skip empty lines */
781 			if (*line == '\0')
782 				continue;
783 
784 			do_host(line);
785 		}
786 
787 		if (ferror(fp))
788 			fatal("%s: %s: %s", __progname, argv[j],
789 			    strerror(errno));
790 
791 		fclose(fp);
792 	}
793 
794 	while (optind < argc)
795 		do_host(argv[optind++]);
796 
797 	while (ncon > 0)
798 		conloop();
799 
800 	return (0);
801 }
802