misc.c revision 240075 
1/* $OpenBSD: misc.c,v 1.86 2011/09/05 05:59:08 djm Exp $ */
2/* $FreeBSD: head/crypto/openssh/misc.c 240075 2012-09-03 16:51:41Z des $ */
3/*
4 * Copyright (c) 2000 Markus Friedl.  All rights reserved.
5 * Copyright (c) 2005,2006 Damien Miller.  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 *
16 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
17 * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
18 * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
19 * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
20 * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
21 * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
22 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
23 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
24 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
25 * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
26 */
27
28#include "includes.h"
29
30#include <sys/types.h>
31#include <sys/ioctl.h>
32#include <sys/socket.h>
33#include <sys/param.h>
34
35#include <stdarg.h>
36#include <stdio.h>
37#include <stdlib.h>
38#include <string.h>
39#include <time.h>
40#include <unistd.h>
41
42#include <netinet/in.h>
43#include <netinet/in_systm.h>
44#include <netinet/ip.h>
45#include <netinet/tcp.h>
46
47#include <errno.h>
48#include <fcntl.h>
49#include <netdb.h>
50#ifdef HAVE_PATHS_H
51# include <paths.h>
52#include <pwd.h>
53#endif
54#ifdef SSH_TUN_OPENBSD
55#include <net/if.h>
56#endif
57
58#include "xmalloc.h"
59#include "misc.h"
60#include "log.h"
61#include "ssh.h"
62
63/* remove newline at end of string */
64char *
65chop(char *s)
66{
67	char *t = s;
68	while (*t) {
69		if (*t == '\n' || *t == '\r') {
70			*t = '\0';
71			return s;
72		}
73		t++;
74	}
75	return s;
76
77}
78
79/* set/unset filedescriptor to non-blocking */
80int
81set_nonblock(int fd)
82{
83	int val;
84
85	val = fcntl(fd, F_GETFL, 0);
86	if (val < 0) {
87		error("fcntl(%d, F_GETFL, 0): %s", fd, strerror(errno));
88		return (-1);
89	}
90	if (val & O_NONBLOCK) {
91		debug3("fd %d is O_NONBLOCK", fd);
92		return (0);
93	}
94	debug2("fd %d setting O_NONBLOCK", fd);
95	val |= O_NONBLOCK;
96	if (fcntl(fd, F_SETFL, val) == -1) {
97		debug("fcntl(%d, F_SETFL, O_NONBLOCK): %s", fd,
98		    strerror(errno));
99		return (-1);
100	}
101	return (0);
102}
103
104int
105unset_nonblock(int fd)
106{
107	int val;
108
109	val = fcntl(fd, F_GETFL, 0);
110	if (val < 0) {
111		error("fcntl(%d, F_GETFL, 0): %s", fd, strerror(errno));
112		return (-1);
113	}
114	if (!(val & O_NONBLOCK)) {
115		debug3("fd %d is not O_NONBLOCK", fd);
116		return (0);
117	}
118	debug("fd %d clearing O_NONBLOCK", fd);
119	val &= ~O_NONBLOCK;
120	if (fcntl(fd, F_SETFL, val) == -1) {
121		debug("fcntl(%d, F_SETFL, ~O_NONBLOCK): %s",
122		    fd, strerror(errno));
123		return (-1);
124	}
125	return (0);
126}
127
128const char *
129ssh_gai_strerror(int gaierr)
130{
131	if (gaierr == EAI_SYSTEM)
132		return strerror(errno);
133	return gai_strerror(gaierr);
134}
135
136/* disable nagle on socket */
137void
138set_nodelay(int fd)
139{
140	int opt;
141	socklen_t optlen;
142
143	optlen = sizeof opt;
144	if (getsockopt(fd, IPPROTO_TCP, TCP_NODELAY, &opt, &optlen) == -1) {
145		debug("getsockopt TCP_NODELAY: %.100s", strerror(errno));
146		return;
147	}
148	if (opt == 1) {
149		debug2("fd %d is TCP_NODELAY", fd);
150		return;
151	}
152	opt = 1;
153	debug2("fd %d setting TCP_NODELAY", fd);
154	if (setsockopt(fd, IPPROTO_TCP, TCP_NODELAY, &opt, sizeof opt) == -1)
155		error("setsockopt TCP_NODELAY: %.100s", strerror(errno));
156}
157
158/* Characters considered whitespace in strsep calls. */
159#define WHITESPACE " \t\r\n"
160#define QUOTE	"\""
161
162/* return next token in configuration line */
163char *
164strdelim(char **s)
165{
166	char *old;
167	int wspace = 0;
168
169	if (*s == NULL)
170		return NULL;
171
172	old = *s;
173
174	*s = strpbrk(*s, WHITESPACE QUOTE "=");
175	if (*s == NULL)
176		return (old);
177
178	if (*s[0] == '\"') {
179		memmove(*s, *s + 1, strlen(*s)); /* move nul too */
180		/* Find matching quote */
181		if ((*s = strpbrk(*s, QUOTE)) == NULL) {
182			return (NULL);		/* no matching quote */
183		} else {
184			*s[0] = '\0';
185			*s += strspn(*s + 1, WHITESPACE) + 1;
186			return (old);
187		}
188	}
189
190	/* Allow only one '=' to be skipped */
191	if (*s[0] == '=')
192		wspace = 1;
193	*s[0] = '\0';
194
195	/* Skip any extra whitespace after first token */
196	*s += strspn(*s + 1, WHITESPACE) + 1;
197	if (*s[0] == '=' && !wspace)
198		*s += strspn(*s + 1, WHITESPACE) + 1;
199
200	return (old);
201}
202
203struct passwd *
204pwcopy(struct passwd *pw)
205{
206	struct passwd *copy = xcalloc(1, sizeof(*copy));
207
208	copy->pw_name = xstrdup(pw->pw_name);
209	copy->pw_passwd = xstrdup(pw->pw_passwd);
210	copy->pw_gecos = xstrdup(pw->pw_gecos);
211	copy->pw_uid = pw->pw_uid;
212	copy->pw_gid = pw->pw_gid;
213#ifdef HAVE_PW_EXPIRE_IN_PASSWD
214	copy->pw_expire = pw->pw_expire;
215#endif
216#ifdef HAVE_PW_CHANGE_IN_PASSWD
217	copy->pw_change = pw->pw_change;
218#endif
219#ifdef HAVE_PW_CLASS_IN_PASSWD
220	copy->pw_class = xstrdup(pw->pw_class);
221#endif
222	copy->pw_dir = xstrdup(pw->pw_dir);
223	copy->pw_shell = xstrdup(pw->pw_shell);
224	return copy;
225}
226
227/*
228 * Convert ASCII string to TCP/IP port number.
229 * Port must be >=0 and <=65535.
230 * Return -1 if invalid.
231 */
232int
233a2port(const char *s)
234{
235	long long port;
236	const char *errstr;
237
238	port = strtonum(s, 0, 65535, &errstr);
239	if (errstr != NULL)
240		return -1;
241	return (int)port;
242}
243
244int
245a2tun(const char *s, int *remote)
246{
247	const char *errstr = NULL;
248	char *sp, *ep;
249	int tun;
250
251	if (remote != NULL) {
252		*remote = SSH_TUNID_ANY;
253		sp = xstrdup(s);
254		if ((ep = strchr(sp, ':')) == NULL) {
255			xfree(sp);
256			return (a2tun(s, NULL));
257		}
258		ep[0] = '\0'; ep++;
259		*remote = a2tun(ep, NULL);
260		tun = a2tun(sp, NULL);
261		xfree(sp);
262		return (*remote == SSH_TUNID_ERR ? *remote : tun);
263	}
264
265	if (strcasecmp(s, "any") == 0)
266		return (SSH_TUNID_ANY);
267
268	tun = strtonum(s, 0, SSH_TUNID_MAX, &errstr);
269	if (errstr != NULL)
270		return (SSH_TUNID_ERR);
271
272	return (tun);
273}
274
275#define SECONDS		1
276#define MINUTES		(SECONDS * 60)
277#define HOURS		(MINUTES * 60)
278#define DAYS		(HOURS * 24)
279#define WEEKS		(DAYS * 7)
280
281/*
282 * Convert a time string into seconds; format is
283 * a sequence of:
284 *      time[qualifier]
285 *
286 * Valid time qualifiers are:
287 *      <none>  seconds
288 *      s|S     seconds
289 *      m|M     minutes
290 *      h|H     hours
291 *      d|D     days
292 *      w|W     weeks
293 *
294 * Examples:
295 *      90m     90 minutes
296 *      1h30m   90 minutes
297 *      2d      2 days
298 *      1w      1 week
299 *
300 * Return -1 if time string is invalid.
301 */
302long
303convtime(const char *s)
304{
305	long total, secs;
306	const char *p;
307	char *endp;
308
309	errno = 0;
310	total = 0;
311	p = s;
312
313	if (p == NULL || *p == '\0')
314		return -1;
315
316	while (*p) {
317		secs = strtol(p, &endp, 10);
318		if (p == endp ||
319		    (errno == ERANGE && (secs == LONG_MIN || secs == LONG_MAX)) ||
320		    secs < 0)
321			return -1;
322
323		switch (*endp++) {
324		case '\0':
325			endp--;
326			break;
327		case 's':
328		case 'S':
329			break;
330		case 'm':
331		case 'M':
332			secs *= MINUTES;
333			break;
334		case 'h':
335		case 'H':
336			secs *= HOURS;
337			break;
338		case 'd':
339		case 'D':
340			secs *= DAYS;
341			break;
342		case 'w':
343		case 'W':
344			secs *= WEEKS;
345			break;
346		default:
347			return -1;
348		}
349		total += secs;
350		if (total < 0)
351			return -1;
352		p = endp;
353	}
354
355	return total;
356}
357
358/*
359 * Returns a standardized host+port identifier string.
360 * Caller must free returned string.
361 */
362char *
363put_host_port(const char *host, u_short port)
364{
365	char *hoststr;
366
367	if (port == 0 || port == SSH_DEFAULT_PORT)
368		return(xstrdup(host));
369	if (asprintf(&hoststr, "[%s]:%d", host, (int)port) < 0)
370		fatal("put_host_port: asprintf: %s", strerror(errno));
371	debug3("put_host_port: %s", hoststr);
372	return hoststr;
373}
374
375/*
376 * Search for next delimiter between hostnames/addresses and ports.
377 * Argument may be modified (for termination).
378 * Returns *cp if parsing succeeds.
379 * *cp is set to the start of the next delimiter, if one was found.
380 * If this is the last field, *cp is set to NULL.
381 */
382char *
383hpdelim(char **cp)
384{
385	char *s, *old;
386
387	if (cp == NULL || *cp == NULL)
388		return NULL;
389
390	old = s = *cp;
391	if (*s == '[') {
392		if ((s = strchr(s, ']')) == NULL)
393			return NULL;
394		else
395			s++;
396	} else if ((s = strpbrk(s, ":/")) == NULL)
397		s = *cp + strlen(*cp); /* skip to end (see first case below) */
398
399	switch (*s) {
400	case '\0':
401		*cp = NULL;	/* no more fields*/
402		break;
403
404	case ':':
405	case '/':
406		*s = '\0';	/* terminate */
407		*cp = s + 1;
408		break;
409
410	default:
411		return NULL;
412	}
413
414	return old;
415}
416
417char *
418cleanhostname(char *host)
419{
420	if (*host == '[' && host[strlen(host) - 1] == ']') {
421		host[strlen(host) - 1] = '\0';
422		return (host + 1);
423	} else
424		return host;
425}
426
427char *
428colon(char *cp)
429{
430	int flag = 0;
431
432	if (*cp == ':')		/* Leading colon is part of file name. */
433		return NULL;
434	if (*cp == '[')
435		flag = 1;
436
437	for (; *cp; ++cp) {
438		if (*cp == '@' && *(cp+1) == '[')
439			flag = 1;
440		if (*cp == ']' && *(cp+1) == ':' && flag)
441			return (cp+1);
442		if (*cp == ':' && !flag)
443			return (cp);
444		if (*cp == '/')
445			return NULL;
446	}
447	return NULL;
448}
449
450/* function to assist building execv() arguments */
451void
452addargs(arglist *args, char *fmt, ...)
453{
454	va_list ap;
455	char *cp;
456	u_int nalloc;
457	int r;
458
459	va_start(ap, fmt);
460	r = vasprintf(&cp, fmt, ap);
461	va_end(ap);
462	if (r == -1)
463		fatal("addargs: argument too long");
464
465	nalloc = args->nalloc;
466	if (args->list == NULL) {
467		nalloc = 32;
468		args->num = 0;
469	} else if (args->num+2 >= nalloc)
470		nalloc *= 2;
471
472	args->list = xrealloc(args->list, nalloc, sizeof(char *));
473	args->nalloc = nalloc;
474	args->list[args->num++] = cp;
475	args->list[args->num] = NULL;
476}
477
478void
479replacearg(arglist *args, u_int which, char *fmt, ...)
480{
481	va_list ap;
482	char *cp;
483	int r;
484
485	va_start(ap, fmt);
486	r = vasprintf(&cp, fmt, ap);
487	va_end(ap);
488	if (r == -1)
489		fatal("replacearg: argument too long");
490
491	if (which >= args->num)
492		fatal("replacearg: tried to replace invalid arg %d >= %d",
493		    which, args->num);
494	xfree(args->list[which]);
495	args->list[which] = cp;
496}
497
498void
499freeargs(arglist *args)
500{
501	u_int i;
502
503	if (args->list != NULL) {
504		for (i = 0; i < args->num; i++)
505			xfree(args->list[i]);
506		xfree(args->list);
507		args->nalloc = args->num = 0;
508		args->list = NULL;
509	}
510}
511
512/*
513 * Expands tildes in the file name.  Returns data allocated by xmalloc.
514 * Warning: this calls getpw*.
515 */
516char *
517tilde_expand_filename(const char *filename, uid_t uid)
518{
519	const char *path;
520	char user[128], ret[MAXPATHLEN];
521	struct passwd *pw;
522	u_int len, slash;
523
524	if (*filename != '~')
525		return (xstrdup(filename));
526	filename++;
527
528	path = strchr(filename, '/');
529	if (path != NULL && path > filename) {		/* ~user/path */
530		slash = path - filename;
531		if (slash > sizeof(user) - 1)
532			fatal("tilde_expand_filename: ~username too long");
533		memcpy(user, filename, slash);
534		user[slash] = '\0';
535		if ((pw = getpwnam(user)) == NULL)
536			fatal("tilde_expand_filename: No such user %s", user);
537	} else if ((pw = getpwuid(uid)) == NULL)	/* ~/path */
538		fatal("tilde_expand_filename: No such uid %ld", (long)uid);
539
540	if (strlcpy(ret, pw->pw_dir, sizeof(ret)) >= sizeof(ret))
541		fatal("tilde_expand_filename: Path too long");
542
543	/* Make sure directory has a trailing '/' */
544	len = strlen(pw->pw_dir);
545	if ((len == 0 || pw->pw_dir[len - 1] != '/') &&
546	    strlcat(ret, "/", sizeof(ret)) >= sizeof(ret))
547		fatal("tilde_expand_filename: Path too long");
548
549	/* Skip leading '/' from specified path */
550	if (path != NULL)
551		filename = path + 1;
552	if (strlcat(ret, filename, sizeof(ret)) >= sizeof(ret))
553		fatal("tilde_expand_filename: Path too long");
554
555	return (xstrdup(ret));
556}
557
558/*
559 * Expand a string with a set of %[char] escapes. A number of escapes may be
560 * specified as (char *escape_chars, char *replacement) pairs. The list must
561 * be terminated by a NULL escape_char. Returns replaced string in memory
562 * allocated by xmalloc.
563 */
564char *
565percent_expand(const char *string, ...)
566{
567#define EXPAND_MAX_KEYS	16
568	u_int num_keys, i, j;
569	struct {
570		const char *key;
571		const char *repl;
572	} keys[EXPAND_MAX_KEYS];
573	char buf[4096];
574	va_list ap;
575
576	/* Gather keys */
577	va_start(ap, string);
578	for (num_keys = 0; num_keys < EXPAND_MAX_KEYS; num_keys++) {
579		keys[num_keys].key = va_arg(ap, char *);
580		if (keys[num_keys].key == NULL)
581			break;
582		keys[num_keys].repl = va_arg(ap, char *);
583		if (keys[num_keys].repl == NULL)
584			fatal("%s: NULL replacement", __func__);
585	}
586	if (num_keys == EXPAND_MAX_KEYS && va_arg(ap, char *) != NULL)
587		fatal("%s: too many keys", __func__);
588	va_end(ap);
589
590	/* Expand string */
591	*buf = '\0';
592	for (i = 0; *string != '\0'; string++) {
593		if (*string != '%') {
594 append:
595			buf[i++] = *string;
596			if (i >= sizeof(buf))
597				fatal("%s: string too long", __func__);
598			buf[i] = '\0';
599			continue;
600		}
601		string++;
602		/* %% case */
603		if (*string == '%')
604			goto append;
605		for (j = 0; j < num_keys; j++) {
606			if (strchr(keys[j].key, *string) != NULL) {
607				i = strlcat(buf, keys[j].repl, sizeof(buf));
608				if (i >= sizeof(buf))
609					fatal("%s: string too long", __func__);
610				break;
611			}
612		}
613		if (j >= num_keys)
614			fatal("%s: unknown key %%%c", __func__, *string);
615	}
616	return (xstrdup(buf));
617#undef EXPAND_MAX_KEYS
618}
619
620/*
621 * Read an entire line from a public key file into a static buffer, discarding
622 * lines that exceed the buffer size.  Returns 0 on success, -1 on failure.
623 */
624int
625read_keyfile_line(FILE *f, const char *filename, char *buf, size_t bufsz,
626   u_long *lineno)
627{
628	while (fgets(buf, bufsz, f) != NULL) {
629		if (buf[0] == '\0')
630			continue;
631		(*lineno)++;
632		if (buf[strlen(buf) - 1] == '\n' || feof(f)) {
633			return 0;
634		} else {
635			debug("%s: %s line %lu exceeds size limit", __func__,
636			    filename, *lineno);
637			/* discard remainder of line */
638			while (fgetc(f) != '\n' && !feof(f))
639				;	/* nothing */
640		}
641	}
642	return -1;
643}
644
645int
646tun_open(int tun, int mode)
647{
648#if defined(CUSTOM_SYS_TUN_OPEN)
649	return (sys_tun_open(tun, mode));
650#elif defined(SSH_TUN_OPENBSD)
651	struct ifreq ifr;
652	char name[100];
653	int fd = -1, sock;
654
655	/* Open the tunnel device */
656	if (tun <= SSH_TUNID_MAX) {
657		snprintf(name, sizeof(name), "/dev/tun%d", tun);
658		fd = open(name, O_RDWR);
659	} else if (tun == SSH_TUNID_ANY) {
660		for (tun = 100; tun >= 0; tun--) {
661			snprintf(name, sizeof(name), "/dev/tun%d", tun);
662			if ((fd = open(name, O_RDWR)) >= 0)
663				break;
664		}
665	} else {
666		debug("%s: invalid tunnel %u", __func__, tun);
667		return (-1);
668	}
669
670	if (fd < 0) {
671		debug("%s: %s open failed: %s", __func__, name, strerror(errno));
672		return (-1);
673	}
674
675	debug("%s: %s mode %d fd %d", __func__, name, mode, fd);
676
677	/* Set the tunnel device operation mode */
678	snprintf(ifr.ifr_name, sizeof(ifr.ifr_name), "tun%d", tun);
679	if ((sock = socket(PF_UNIX, SOCK_STREAM, 0)) == -1)
680		goto failed;
681
682	if (ioctl(sock, SIOCGIFFLAGS, &ifr) == -1)
683		goto failed;
684
685	/* Set interface mode */
686	ifr.ifr_flags &= ~IFF_UP;
687	if (mode == SSH_TUNMODE_ETHERNET)
688		ifr.ifr_flags |= IFF_LINK0;
689	else
690		ifr.ifr_flags &= ~IFF_LINK0;
691	if (ioctl(sock, SIOCSIFFLAGS, &ifr) == -1)
692		goto failed;
693
694	/* Bring interface up */
695	ifr.ifr_flags |= IFF_UP;
696	if (ioctl(sock, SIOCSIFFLAGS, &ifr) == -1)
697		goto failed;
698
699	close(sock);
700	return (fd);
701
702 failed:
703	if (fd >= 0)
704		close(fd);
705	if (sock >= 0)
706		close(sock);
707	debug("%s: failed to set %s mode %d: %s", __func__, name,
708	    mode, strerror(errno));
709	return (-1);
710#else
711	error("Tunnel interfaces are not supported on this platform");
712	return (-1);
713#endif
714}
715
716void
717sanitise_stdfd(void)
718{
719	int nullfd, dupfd;
720
721	if ((nullfd = dupfd = open(_PATH_DEVNULL, O_RDWR)) == -1) {
722		fprintf(stderr, "Couldn't open /dev/null: %s\n",
723		    strerror(errno));
724		exit(1);
725	}
726	while (++dupfd <= 2) {
727		/* Only clobber closed fds */
728		if (fcntl(dupfd, F_GETFL, 0) >= 0)
729			continue;
730		if (dup2(nullfd, dupfd) == -1) {
731			fprintf(stderr, "dup2: %s\n", strerror(errno));
732			exit(1);
733		}
734	}
735	if (nullfd > 2)
736		close(nullfd);
737}
738
739char *
740tohex(const void *vp, size_t l)
741{
742	const u_char *p = (const u_char *)vp;
743	char b[3], *r;
744	size_t i, hl;
745
746	if (l > 65536)
747		return xstrdup("tohex: length > 65536");
748
749	hl = l * 2 + 1;
750	r = xcalloc(1, hl);
751	for (i = 0; i < l; i++) {
752		snprintf(b, sizeof(b), "%02x", p[i]);
753		strlcat(r, b, hl);
754	}
755	return (r);
756}
757
758u_int64_t
759get_u64(const void *vp)
760{
761	const u_char *p = (const u_char *)vp;
762	u_int64_t v;
763
764	v  = (u_int64_t)p[0] << 56;
765	v |= (u_int64_t)p[1] << 48;
766	v |= (u_int64_t)p[2] << 40;
767	v |= (u_int64_t)p[3] << 32;
768	v |= (u_int64_t)p[4] << 24;
769	v |= (u_int64_t)p[5] << 16;
770	v |= (u_int64_t)p[6] << 8;
771	v |= (u_int64_t)p[7];
772
773	return (v);
774}
775
776u_int32_t
777get_u32(const void *vp)
778{
779	const u_char *p = (const u_char *)vp;
780	u_int32_t v;
781
782	v  = (u_int32_t)p[0] << 24;
783	v |= (u_int32_t)p[1] << 16;
784	v |= (u_int32_t)p[2] << 8;
785	v |= (u_int32_t)p[3];
786
787	return (v);
788}
789
790u_int16_t
791get_u16(const void *vp)
792{
793	const u_char *p = (const u_char *)vp;
794	u_int16_t v;
795
796	v  = (u_int16_t)p[0] << 8;
797	v |= (u_int16_t)p[1];
798
799	return (v);
800}
801
802void
803put_u64(void *vp, u_int64_t v)
804{
805	u_char *p = (u_char *)vp;
806
807	p[0] = (u_char)(v >> 56) & 0xff;
808	p[1] = (u_char)(v >> 48) & 0xff;
809	p[2] = (u_char)(v >> 40) & 0xff;
810	p[3] = (u_char)(v >> 32) & 0xff;
811	p[4] = (u_char)(v >> 24) & 0xff;
812	p[5] = (u_char)(v >> 16) & 0xff;
813	p[6] = (u_char)(v >> 8) & 0xff;
814	p[7] = (u_char)v & 0xff;
815}
816
817void
818put_u32(void *vp, u_int32_t v)
819{
820	u_char *p = (u_char *)vp;
821
822	p[0] = (u_char)(v >> 24) & 0xff;
823	p[1] = (u_char)(v >> 16) & 0xff;
824	p[2] = (u_char)(v >> 8) & 0xff;
825	p[3] = (u_char)v & 0xff;
826}
827
828
829void
830put_u16(void *vp, u_int16_t v)
831{
832	u_char *p = (u_char *)vp;
833
834	p[0] = (u_char)(v >> 8) & 0xff;
835	p[1] = (u_char)v & 0xff;
836}
837
838void
839ms_subtract_diff(struct timeval *start, int *ms)
840{
841	struct timeval diff, finish;
842
843	gettimeofday(&finish, NULL);
844	timersub(&finish, start, &diff);
845	*ms -= (diff.tv_sec * 1000) + (diff.tv_usec / 1000);
846}
847
848void
849ms_to_timeval(struct timeval *tv, int ms)
850{
851	if (ms < 0)
852		ms = 0;
853	tv->tv_sec = ms / 1000;
854	tv->tv_usec = (ms % 1000) * 1000;
855}
856
857void
858bandwidth_limit_init(struct bwlimit *bw, u_int64_t kbps, size_t buflen)
859{
860	bw->buflen = buflen;
861	bw->rate = kbps;
862	bw->thresh = bw->rate;
863	bw->lamt = 0;
864	timerclear(&bw->bwstart);
865	timerclear(&bw->bwend);
866}
867
868/* Callback from read/write loop to insert bandwidth-limiting delays */
869void
870bandwidth_limit(struct bwlimit *bw, size_t read_len)
871{
872	u_int64_t waitlen;
873	struct timespec ts, rm;
874
875	if (!timerisset(&bw->bwstart)) {
876		gettimeofday(&bw->bwstart, NULL);
877		return;
878	}
879
880	bw->lamt += read_len;
881	if (bw->lamt < bw->thresh)
882		return;
883
884	gettimeofday(&bw->bwend, NULL);
885	timersub(&bw->bwend, &bw->bwstart, &bw->bwend);
886	if (!timerisset(&bw->bwend))
887		return;
888
889	bw->lamt *= 8;
890	waitlen = (double)1000000L * bw->lamt / bw->rate;
891
892	bw->bwstart.tv_sec = waitlen / 1000000L;
893	bw->bwstart.tv_usec = waitlen % 1000000L;
894
895	if (timercmp(&bw->bwstart, &bw->bwend, >)) {
896		timersub(&bw->bwstart, &bw->bwend, &bw->bwend);
897
898		/* Adjust the wait time */
899		if (bw->bwend.tv_sec) {
900			bw->thresh /= 2;
901			if (bw->thresh < bw->buflen / 4)
902				bw->thresh = bw->buflen / 4;
903		} else if (bw->bwend.tv_usec < 10000) {
904			bw->thresh *= 2;
905			if (bw->thresh > bw->buflen * 8)
906				bw->thresh = bw->buflen * 8;
907		}
908
909		TIMEVAL_TO_TIMESPEC(&bw->bwend, &ts);
910		while (nanosleep(&ts, &rm) == -1) {
911			if (errno != EINTR)
912				break;
913			ts = rm;
914		}
915	}
916
917	bw->lamt = 0;
918	gettimeofday(&bw->bwstart, NULL);
919}
920
921/* Make a template filename for mk[sd]temp() */
922void
923mktemp_proto(char *s, size_t len)
924{
925	const char *tmpdir;
926	int r;
927
928	if ((tmpdir = getenv("TMPDIR")) != NULL) {
929		r = snprintf(s, len, "%s/ssh-XXXXXXXXXXXX", tmpdir);
930		if (r > 0 && (size_t)r < len)
931			return;
932	}
933	r = snprintf(s, len, "/tmp/ssh-XXXXXXXXXXXX");
934	if (r < 0 || (size_t)r >= len)
935		fatal("%s: template string too short", __func__);
936}
937
938static const struct {
939	const char *name;
940	int value;
941} ipqos[] = {
942	{ "af11", IPTOS_DSCP_AF11 },
943	{ "af12", IPTOS_DSCP_AF12 },
944	{ "af13", IPTOS_DSCP_AF13 },
945	{ "af21", IPTOS_DSCP_AF21 },
946	{ "af22", IPTOS_DSCP_AF22 },
947	{ "af23", IPTOS_DSCP_AF23 },
948	{ "af31", IPTOS_DSCP_AF31 },
949	{ "af32", IPTOS_DSCP_AF32 },
950	{ "af33", IPTOS_DSCP_AF33 },
951	{ "af41", IPTOS_DSCP_AF41 },
952	{ "af42", IPTOS_DSCP_AF42 },
953	{ "af43", IPTOS_DSCP_AF43 },
954	{ "cs0", IPTOS_DSCP_CS0 },
955	{ "cs1", IPTOS_DSCP_CS1 },
956	{ "cs2", IPTOS_DSCP_CS2 },
957	{ "cs3", IPTOS_DSCP_CS3 },
958	{ "cs4", IPTOS_DSCP_CS4 },
959	{ "cs5", IPTOS_DSCP_CS5 },
960	{ "cs6", IPTOS_DSCP_CS6 },
961	{ "cs7", IPTOS_DSCP_CS7 },
962	{ "ef", IPTOS_DSCP_EF },
963	{ "lowdelay", IPTOS_LOWDELAY },
964	{ "throughput", IPTOS_THROUGHPUT },
965	{ "reliability", IPTOS_RELIABILITY },
966	{ NULL, -1 }
967};
968
969int
970parse_ipqos(const char *cp)
971{
972	u_int i;
973	char *ep;
974	long val;
975
976	if (cp == NULL)
977		return -1;
978	for (i = 0; ipqos[i].name != NULL; i++) {
979		if (strcasecmp(cp, ipqos[i].name) == 0)
980			return ipqos[i].value;
981	}
982	/* Try parsing as an integer */
983	val = strtol(cp, &ep, 0);
984	if (*cp == '\0' || *ep != '\0' || val < 0 || val > 255)
985		return -1;
986	return val;
987}
988
989const char *
990iptos2str(int iptos)
991{
992	int i;
993	static char iptos_str[sizeof "0xff"];
994
995	for (i = 0; ipqos[i].name != NULL; i++) {
996		if (ipqos[i].value == iptos)
997			return ipqos[i].name;
998	}
999	snprintf(iptos_str, sizeof iptos_str, "0x%02x", iptos);
1000	return iptos_str;
1001}
1002void
1003sock_set_v6only(int s)
1004{
1005#ifdef IPV6_V6ONLY
1006	int on = 1;
1007
1008	debug3("%s: set socket %d IPV6_V6ONLY", __func__, s);
1009	if (setsockopt(s, IPPROTO_IPV6, IPV6_V6ONLY, &on, sizeof(on)) == -1)
1010		error("setsockopt IPV6_V6ONLY: %s", strerror(errno));
1011#endif
1012}
1013
1014void
1015sock_get_rcvbuf(int *size, int rcvbuf)
1016{
1017	int sock, socksize;
1018	socklen_t socksizelen = sizeof(socksize);
1019
1020	/*
1021	 * Create a socket but do not connect it.  We use it
1022	 * only to get the rcv socket size.
1023	 */
1024	sock = socket(AF_INET6, SOCK_STREAM, 0);
1025	if (sock < 0)
1026		sock = socket(AF_INET, SOCK_STREAM, 0);
1027	if (sock < 0)
1028		return;
1029
1030	/*
1031	 * If the tcp_rcv_buf option is set and passed in, attempt to set the
1032	 *  buffer size to its value.
1033	 */
1034	if (rcvbuf)
1035		setsockopt(sock, SOL_SOCKET, SO_RCVBUF, (void *)&rcvbuf,
1036		    sizeof(rcvbuf));
1037
1038	if (getsockopt(sock, SOL_SOCKET, SO_RCVBUF,
1039	    &socksize, &socksizelen) == 0)
1040		if (size != NULL)
1041			*size = socksize;
1042	close(sock);
1043}
1044