1/* $OpenBSD: misc.c,v 1.85 2011/03/29 18:54:17 stevesk Exp $ */
2/*
3 * Copyright (c) 2000 Markus Friedl.  All rights reserved.
4 * Copyright (c) 2005,2006 Damien Miller.  All rights reserved.
5 *
6 * Redistribution and use in source and binary forms, with or without
7 * modification, are permitted provided that the following conditions
8 * are met:
9 * 1. Redistributions of source code must retain the above copyright
10 *    notice, this list of conditions and the following disclaimer.
11 * 2. Redistributions in binary form must reproduce the above copyright
12 *    notice, this list of conditions and the following disclaimer in the
13 *    documentation and/or other materials provided with the distribution.
14 *
15 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
16 * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
17 * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
18 * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
19 * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
20 * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
21 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
22 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
23 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
24 * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
25 */
26
27#include "includes.h"
28
29#include <sys/types.h>
30#include <sys/ioctl.h>
31#include <sys/socket.h>
32#include <sys/param.h>
33
34#include <stdarg.h>
35#include <stdio.h>
36#include <stdlib.h>
37#include <string.h>
38#include <time.h>
39#include <unistd.h>
40
41#include <netinet/in.h>
42#include <netinet/in_systm.h>
43#include <netinet/ip.h>
44#include <netinet/tcp.h>
45
46#include <errno.h>
47#include <fcntl.h>
48#include <netdb.h>
49#ifdef HAVE_PATHS_H
50# include <paths.h>
51#include <pwd.h>
52#endif
53#ifdef SSH_TUN_OPENBSD
54#include <net/if.h>
55#endif
56
57#include "xmalloc.h"
58#include "misc.h"
59#include "log.h"
60#include "ssh.h"
61
62/* remove newline at end of string */
63char *
64chop(char *s)
65{
66	char *t = s;
67	while (*t) {
68		if (*t == '\n' || *t == '\r') {
69			*t = '\0';
70			return s;
71		}
72		t++;
73	}
74	return s;
75
76}
77
78/* set/unset filedescriptor to non-blocking */
79int
80set_nonblock(int fd)
81{
82	int val;
83
84	val = fcntl(fd, F_GETFL, 0);
85	if (val < 0) {
86		error("fcntl(%d, F_GETFL, 0): %s", fd, strerror(errno));
87		return (-1);
88	}
89	if (val & O_NONBLOCK) {
90		debug3("fd %d is O_NONBLOCK", fd);
91		return (0);
92	}
93	debug2("fd %d setting O_NONBLOCK", fd);
94	val |= O_NONBLOCK;
95	if (fcntl(fd, F_SETFL, val) == -1) {
96		debug("fcntl(%d, F_SETFL, O_NONBLOCK): %s", fd,
97		    strerror(errno));
98		return (-1);
99	}
100	return (0);
101}
102
103int
104unset_nonblock(int fd)
105{
106	int val;
107
108	val = fcntl(fd, F_GETFL, 0);
109	if (val < 0) {
110		error("fcntl(%d, F_GETFL, 0): %s", fd, strerror(errno));
111		return (-1);
112	}
113	if (!(val & O_NONBLOCK)) {
114		debug3("fd %d is not O_NONBLOCK", fd);
115		return (0);
116	}
117	debug("fd %d clearing O_NONBLOCK", fd);
118	val &= ~O_NONBLOCK;
119	if (fcntl(fd, F_SETFL, val) == -1) {
120		debug("fcntl(%d, F_SETFL, ~O_NONBLOCK): %s",
121		    fd, strerror(errno));
122		return (-1);
123	}
124	return (0);
125}
126
127const char *
128ssh_gai_strerror(int gaierr)
129{
130	if (gaierr == EAI_SYSTEM)
131		return strerror(errno);
132	return gai_strerror(gaierr);
133}
134
135/* disable nagle on socket */
136void
137set_nodelay(int fd)
138{
139	int opt;
140	socklen_t optlen;
141
142	optlen = sizeof opt;
143	if (getsockopt(fd, IPPROTO_TCP, TCP_NODELAY, &opt, &optlen) == -1) {
144		debug("getsockopt TCP_NODELAY: %.100s", strerror(errno));
145		return;
146	}
147	if (opt == 1) {
148		debug2("fd %d is TCP_NODELAY", fd);
149		return;
150	}
151	opt = 1;
152	debug2("fd %d setting TCP_NODELAY", fd);
153	if (setsockopt(fd, IPPROTO_TCP, TCP_NODELAY, &opt, sizeof opt) == -1)
154		error("setsockopt TCP_NODELAY: %.100s", strerror(errno));
155}
156
157/* Characters considered whitespace in strsep calls. */
158#define WHITESPACE " \t\r\n"
159#define QUOTE	"\""
160
161/* return next token in configuration line */
162char *
163strdelim(char **s)
164{
165	char *old;
166	int wspace = 0;
167
168	if (*s == NULL)
169		return NULL;
170
171	old = *s;
172
173	*s = strpbrk(*s, WHITESPACE QUOTE "=");
174	if (*s == NULL)
175		return (old);
176
177	if (*s[0] == '\"') {
178		memmove(*s, *s + 1, strlen(*s)); /* move nul too */
179		/* Find matching quote */
180		if ((*s = strpbrk(*s, QUOTE)) == NULL) {
181			return (NULL);		/* no matching quote */
182		} else {
183			*s[0] = '\0';
184			*s += strspn(*s + 1, WHITESPACE) + 1;
185			return (old);
186		}
187	}
188
189	/* Allow only one '=' to be skipped */
190	if (*s[0] == '=')
191		wspace = 1;
192	*s[0] = '\0';
193
194	/* Skip any extra whitespace after first token */
195	*s += strspn(*s + 1, WHITESPACE) + 1;
196	if (*s[0] == '=' && !wspace)
197		*s += strspn(*s + 1, WHITESPACE) + 1;
198
199	return (old);
200}
201
202struct passwd *
203pwcopy(struct passwd *pw)
204{
205	struct passwd *copy = xcalloc(1, sizeof(*copy));
206
207	copy->pw_name = xstrdup(pw->pw_name);
208	copy->pw_passwd = pw->pw_passwd ? xstrdup(pw->pw_passwd) : NULL;
209#ifdef HAVE_PW_GECOS_IN_PASSWD
210	copy->pw_gecos = xstrdup(pw->pw_gecos);
211#endif
212	copy->pw_uid = pw->pw_uid;
213	copy->pw_gid = pw->pw_gid;
214#ifdef HAVE_PW_EXPIRE_IN_PASSWD
215	copy->pw_expire = pw->pw_expire;
216#endif
217#ifdef HAVE_PW_CHANGE_IN_PASSWD
218	copy->pw_change = pw->pw_change;
219#endif
220#ifdef HAVE_PW_CLASS_IN_PASSWD
221	copy->pw_class = xstrdup(pw->pw_class);
222#endif
223	copy->pw_dir = xstrdup(pw->pw_dir);
224	copy->pw_shell = xstrdup(pw->pw_shell);
225	return copy;
226}
227
228/*
229 * Convert ASCII string to TCP/IP port number.
230 * Port must be >=0 and <=65535.
231 * Return -1 if invalid.
232 */
233int
234a2port(const char *s)
235{
236	long long port;
237	const char *errstr;
238
239	port = strtonum(s, 0, 65535, &errstr);
240	if (errstr != NULL)
241		return -1;
242	return (int)port;
243}
244
245int
246a2tun(const char *s, int *remote)
247{
248	const char *errstr = NULL;
249	char *sp, *ep;
250	int tun;
251
252	if (remote != NULL) {
253		*remote = SSH_TUNID_ANY;
254		sp = xstrdup(s);
255		if ((ep = strchr(sp, ':')) == NULL) {
256			xfree(sp);
257			return (a2tun(s, NULL));
258		}
259		ep[0] = '\0'; ep++;
260		*remote = a2tun(ep, NULL);
261		tun = a2tun(sp, NULL);
262		xfree(sp);
263		return (*remote == SSH_TUNID_ERR ? *remote : tun);
264	}
265
266	if (strcasecmp(s, "any") == 0)
267		return (SSH_TUNID_ANY);
268
269	tun = strtonum(s, 0, SSH_TUNID_MAX, &errstr);
270	if (errstr != NULL)
271		return (SSH_TUNID_ERR);
272
273	return (tun);
274}
275
276#define SECONDS		1
277#define MINUTES		(SECONDS * 60)
278#define HOURS		(MINUTES * 60)
279#define DAYS		(HOURS * 24)
280#define WEEKS		(DAYS * 7)
281
282/*
283 * Convert a time string into seconds; format is
284 * a sequence of:
285 *      time[qualifier]
286 *
287 * Valid time qualifiers are:
288 *      <none>  seconds
289 *      s|S     seconds
290 *      m|M     minutes
291 *      h|H     hours
292 *      d|D     days
293 *      w|W     weeks
294 *
295 * Examples:
296 *      90m     90 minutes
297 *      1h30m   90 minutes
298 *      2d      2 days
299 *      1w      1 week
300 *
301 * Return -1 if time string is invalid.
302 */
303long
304convtime(const char *s)
305{
306	long total, secs;
307	const char *p;
308	char *endp;
309
310	errno = 0;
311	total = 0;
312	p = s;
313
314	if (p == NULL || *p == '\0')
315		return -1;
316
317	while (*p) {
318		secs = strtol(p, &endp, 10);
319		if (p == endp ||
320		    (errno == ERANGE && (secs == LONG_MIN || secs == LONG_MAX)) ||
321		    secs < 0)
322			return -1;
323
324		switch (*endp++) {
325		case '\0':
326			endp--;
327			break;
328		case 's':
329		case 'S':
330			break;
331		case 'm':
332		case 'M':
333			secs *= MINUTES;
334			break;
335		case 'h':
336		case 'H':
337			secs *= HOURS;
338			break;
339		case 'd':
340		case 'D':
341			secs *= DAYS;
342			break;
343		case 'w':
344		case 'W':
345			secs *= WEEKS;
346			break;
347		default:
348			return -1;
349		}
350		total += secs;
351		if (total < 0)
352			return -1;
353		p = endp;
354	}
355
356	return total;
357}
358
359/*
360 * Returns a standardized host+port identifier string.
361 * Caller must free returned string.
362 */
363char *
364put_host_port(const char *host, u_short port)
365{
366	char *hoststr;
367
368	if (port == 0 || port == SSH_DEFAULT_PORT)
369		return(xstrdup(host));
370	if (asprintf(&hoststr, "[%s]:%d", host, (int)port) < 0)
371		fatal("put_host_port: asprintf: %s", strerror(errno));
372	debug3("put_host_port: %s", hoststr);
373	return hoststr;
374}
375
376/*
377 * Search for next delimiter between hostnames/addresses and ports.
378 * Argument may be modified (for termination).
379 * Returns *cp if parsing succeeds.
380 * *cp is set to the start of the next delimiter, if one was found.
381 * If this is the last field, *cp is set to NULL.
382 */
383char *
384hpdelim(char **cp)
385{
386	char *s, *old;
387
388	if (cp == NULL || *cp == NULL)
389		return NULL;
390
391	old = s = *cp;
392	if (*s == '[') {
393		if ((s = strchr(s, ']')) == NULL)
394			return NULL;
395		else
396			s++;
397	} else if ((s = strpbrk(s, ":/")) == NULL)
398		s = *cp + strlen(*cp); /* skip to end (see first case below) */
399
400	switch (*s) {
401	case '\0':
402		*cp = NULL;	/* no more fields*/
403		break;
404
405	case ':':
406	case '/':
407		*s = '\0';	/* terminate */
408		*cp = s + 1;
409		break;
410
411	default:
412		return NULL;
413	}
414
415	return old;
416}
417
418char *
419cleanhostname(char *host)
420{
421	if (*host == '[' && host[strlen(host) - 1] == ']') {
422		host[strlen(host) - 1] = '\0';
423		return (host + 1);
424	} else
425		return host;
426}
427
428char *
429colon(char *cp)
430{
431	int flag = 0;
432
433	if (*cp == ':')		/* Leading colon is part of file name. */
434		return NULL;
435	if (*cp == '[')
436		flag = 1;
437
438	for (; *cp; ++cp) {
439		if (*cp == '@' && *(cp+1) == '[')
440			flag = 1;
441		if (*cp == ']' && *(cp+1) == ':' && flag)
442			return (cp+1);
443		if (*cp == ':' && !flag)
444			return (cp);
445		if (*cp == '/')
446			return NULL;
447	}
448	return NULL;
449}
450
451/* function to assist building execv() arguments */
452void
453addargs(arglist *args, char *fmt, ...)
454{
455	va_list ap;
456	char *cp;
457	u_int nalloc;
458	int r;
459
460	va_start(ap, fmt);
461	r = vasprintf(&cp, fmt, ap);
462	va_end(ap);
463	if (r == -1)
464		fatal("addargs: argument too long");
465
466	nalloc = args->nalloc;
467	if (args->list == NULL) {
468		nalloc = 32;
469		args->num = 0;
470	} else if (args->num+2 >= nalloc)
471		nalloc *= 2;
472
473	args->list = xrealloc(args->list, nalloc, sizeof(char *));
474	args->nalloc = nalloc;
475	args->list[args->num++] = cp;
476	args->list[args->num] = NULL;
477}
478
479void
480replacearg(arglist *args, u_int which, char *fmt, ...)
481{
482	va_list ap;
483	char *cp;
484	int r;
485
486	va_start(ap, fmt);
487	r = vasprintf(&cp, fmt, ap);
488	va_end(ap);
489	if (r == -1)
490		fatal("replacearg: argument too long");
491
492	if (which >= args->num)
493		fatal("replacearg: tried to replace invalid arg %d >= %d",
494		    which, args->num);
495	xfree(args->list[which]);
496	args->list[which] = cp;
497}
498
499void
500freeargs(arglist *args)
501{
502	u_int i;
503
504	if (args->list != NULL) {
505		for (i = 0; i < args->num; i++)
506			xfree(args->list[i]);
507		xfree(args->list);
508		args->nalloc = args->num = 0;
509		args->list = NULL;
510	}
511}
512
513/*
514 * Expands tildes in the file name.  Returns data allocated by xmalloc.
515 * Warning: this calls getpw*.
516 */
517char *
518tilde_expand_filename(const char *filename, uid_t uid)
519{
520	const char *path;
521	char user[128], ret[MAXPATHLEN];
522	struct passwd *pw;
523	u_int len, slash;
524
525	if (*filename != '~')
526		return (xstrdup(filename));
527	filename++;
528
529	path = strchr(filename, '/');
530	if (path != NULL && path > filename) {		/* ~user/path */
531		slash = path - filename;
532		if (slash > sizeof(user) - 1)
533			fatal("tilde_expand_filename: ~username too long");
534		memcpy(user, filename, slash);
535		user[slash] = '\0';
536		if ((pw = getpwnam(user)) == NULL)
537			fatal("tilde_expand_filename: No such user %s", user);
538	} else if ((pw = getpwuid(uid)) == NULL)	/* ~/path */
539		fatal("tilde_expand_filename: No such uid %ld", (long)uid);
540
541	if (strlcpy(ret, pw->pw_dir, sizeof(ret)) >= sizeof(ret))
542		fatal("tilde_expand_filename: Path too long");
543
544	/* Make sure directory has a trailing '/' */
545	len = strlen(pw->pw_dir);
546	if ((len == 0 || pw->pw_dir[len - 1] != '/') &&
547	    strlcat(ret, "/", sizeof(ret)) >= sizeof(ret))
548		fatal("tilde_expand_filename: Path too long");
549
550	/* Skip leading '/' from specified path */
551	if (path != NULL)
552		filename = path + 1;
553	if (strlcat(ret, filename, sizeof(ret)) >= sizeof(ret))
554		fatal("tilde_expand_filename: Path too long");
555
556	return (xstrdup(ret));
557}
558
559/*
560 * Expand a string with a set of %[char] escapes. A number of escapes may be
561 * specified as (char *escape_chars, char *replacement) pairs. The list must
562 * be terminated by a NULL escape_char. Returns replaced string in memory
563 * allocated by xmalloc.
564 */
565char *
566percent_expand(const char *string, ...)
567{
568#define EXPAND_MAX_KEYS	16
569	u_int num_keys, i, j;
570	struct {
571		const char *key;
572		const char *repl;
573	} keys[EXPAND_MAX_KEYS];
574	char buf[4096];
575	va_list ap;
576
577	/* Gather keys */
578	va_start(ap, string);
579	for (num_keys = 0; num_keys < EXPAND_MAX_KEYS; num_keys++) {
580		keys[num_keys].key = va_arg(ap, char *);
581		if (keys[num_keys].key == NULL)
582			break;
583		keys[num_keys].repl = va_arg(ap, char *);
584		if (keys[num_keys].repl == NULL)
585			fatal("%s: NULL replacement", __func__);
586	}
587	if (num_keys == EXPAND_MAX_KEYS && va_arg(ap, char *) != NULL)
588		fatal("%s: too many keys", __func__);
589	va_end(ap);
590
591	/* Expand string */
592	*buf = '\0';
593	for (i = 0; *string != '\0'; string++) {
594		if (*string != '%') {
595 append:
596			buf[i++] = *string;
597			if (i >= sizeof(buf))
598				fatal("%s: string too long", __func__);
599			buf[i] = '\0';
600			continue;
601		}
602		string++;
603		/* %% case */
604		if (*string == '%')
605			goto append;
606		for (j = 0; j < num_keys; j++) {
607			if (strchr(keys[j].key, *string) != NULL) {
608				i = strlcat(buf, keys[j].repl, sizeof(buf));
609				if (i >= sizeof(buf))
610					fatal("%s: string too long", __func__);
611				break;
612			}
613		}
614		if (j >= num_keys)
615			fatal("%s: unknown key %%%c", __func__, *string);
616	}
617	return (xstrdup(buf));
618#undef EXPAND_MAX_KEYS
619}
620
621/*
622 * Read an entire line from a public key file into a static buffer, discarding
623 * lines that exceed the buffer size.  Returns 0 on success, -1 on failure.
624 */
625int
626read_keyfile_line(FILE *f, const char *filename, char *buf, size_t bufsz,
627   u_long *lineno)
628{
629	while (fgets(buf, bufsz, f) != NULL) {
630		if (buf[0] == '\0')
631			continue;
632		(*lineno)++;
633		if (buf[strlen(buf) - 1] == '\n' || feof(f)) {
634			return 0;
635		} else {
636			debug("%s: %s line %lu exceeds size limit", __func__,
637			    filename, *lineno);
638			/* discard remainder of line */
639			while (fgetc(f) != '\n' && !feof(f))
640				;	/* nothing */
641		}
642	}
643	return -1;
644}
645
646int
647tun_open(int tun, int mode)
648{
649#if defined(CUSTOM_SYS_TUN_OPEN)
650	return (sys_tun_open(tun, mode));
651#elif defined(SSH_TUN_OPENBSD)
652	struct ifreq ifr;
653	char name[100];
654	int fd = -1, sock;
655
656	/* Open the tunnel device */
657	if (tun <= SSH_TUNID_MAX) {
658		snprintf(name, sizeof(name), "/dev/tun%d", tun);
659		fd = open(name, O_RDWR);
660	} else if (tun == SSH_TUNID_ANY) {
661		for (tun = 100; tun >= 0; tun--) {
662			snprintf(name, sizeof(name), "/dev/tun%d", tun);
663			if ((fd = open(name, O_RDWR)) >= 0)
664				break;
665		}
666	} else {
667		debug("%s: invalid tunnel %u", __func__, tun);
668		return (-1);
669	}
670
671	if (fd < 0) {
672		debug("%s: %s open failed: %s", __func__, name, strerror(errno));
673		return (-1);
674	}
675
676	debug("%s: %s mode %d fd %d", __func__, name, mode, fd);
677
678	/* Set the tunnel device operation mode */
679	snprintf(ifr.ifr_name, sizeof(ifr.ifr_name), "tun%d", tun);
680	if ((sock = socket(PF_UNIX, SOCK_STREAM, 0)) == -1)
681		goto failed;
682
683	if (ioctl(sock, SIOCGIFFLAGS, &ifr) == -1)
684		goto failed;
685
686	/* Set interface mode */
687	ifr.ifr_flags &= ~IFF_UP;
688	if (mode == SSH_TUNMODE_ETHERNET)
689		ifr.ifr_flags |= IFF_LINK0;
690	else
691		ifr.ifr_flags &= ~IFF_LINK0;
692	if (ioctl(sock, SIOCSIFFLAGS, &ifr) == -1)
693		goto failed;
694
695	/* Bring interface up */
696	ifr.ifr_flags |= IFF_UP;
697	if (ioctl(sock, SIOCSIFFLAGS, &ifr) == -1)
698		goto failed;
699
700	close(sock);
701	return (fd);
702
703 failed:
704	if (fd >= 0)
705		close(fd);
706	if (sock >= 0)
707		close(sock);
708	debug("%s: failed to set %s mode %d: %s", __func__, name,
709	    mode, strerror(errno));
710	return (-1);
711#else
712	error("Tunnel interfaces are not supported on this platform");
713	return (-1);
714#endif
715}
716
717void
718sanitise_stdfd(void)
719{
720	int nullfd, dupfd;
721
722	if ((nullfd = dupfd = open(_PATH_DEVNULL, O_RDWR)) == -1) {
723		fprintf(stderr, "Couldn't open /dev/null: %s\n",
724		    strerror(errno));
725		exit(1);
726	}
727	while (++dupfd <= 2) {
728		/* Only clobber closed fds */
729		if (fcntl(dupfd, F_GETFL, 0) >= 0)
730			continue;
731		if (dup2(nullfd, dupfd) == -1) {
732			fprintf(stderr, "dup2: %s\n", strerror(errno));
733			exit(1);
734		}
735	}
736	if (nullfd > 2)
737		close(nullfd);
738}
739
740char *
741tohex(const void *vp, size_t l)
742{
743	const u_char *p = (const u_char *)vp;
744	char b[3], *r;
745	size_t i, hl;
746
747	if (l > 65536)
748		return xstrdup("tohex: length > 65536");
749
750	hl = l * 2 + 1;
751	r = xcalloc(1, hl);
752	for (i = 0; i < l; i++) {
753		snprintf(b, sizeof(b), "%02x", p[i]);
754		strlcat(r, b, hl);
755	}
756	return (r);
757}
758
759u_int64_t
760get_u64(const void *vp)
761{
762	const u_char *p = (const u_char *)vp;
763	u_int64_t v;
764
765	v  = (u_int64_t)p[0] << 56;
766	v |= (u_int64_t)p[1] << 48;
767	v |= (u_int64_t)p[2] << 40;
768	v |= (u_int64_t)p[3] << 32;
769	v |= (u_int64_t)p[4] << 24;
770	v |= (u_int64_t)p[5] << 16;
771	v |= (u_int64_t)p[6] << 8;
772	v |= (u_int64_t)p[7];
773
774	return (v);
775}
776
777u_int32_t
778get_u32(const void *vp)
779{
780	const u_char *p = (const u_char *)vp;
781	u_int32_t v;
782
783	v  = (u_int32_t)p[0] << 24;
784	v |= (u_int32_t)p[1] << 16;
785	v |= (u_int32_t)p[2] << 8;
786	v |= (u_int32_t)p[3];
787
788	return (v);
789}
790
791u_int16_t
792get_u16(const void *vp)
793{
794	const u_char *p = (const u_char *)vp;
795	u_int16_t v;
796
797	v  = (u_int16_t)p[0] << 8;
798	v |= (u_int16_t)p[1];
799
800	return (v);
801}
802
803void
804put_u64(void *vp, u_int64_t v)
805{
806	u_char *p = (u_char *)vp;
807
808	p[0] = (u_char)(v >> 56) & 0xff;
809	p[1] = (u_char)(v >> 48) & 0xff;
810	p[2] = (u_char)(v >> 40) & 0xff;
811	p[3] = (u_char)(v >> 32) & 0xff;
812	p[4] = (u_char)(v >> 24) & 0xff;
813	p[5] = (u_char)(v >> 16) & 0xff;
814	p[6] = (u_char)(v >> 8) & 0xff;
815	p[7] = (u_char)v & 0xff;
816}
817
818void
819put_u32(void *vp, u_int32_t v)
820{
821	u_char *p = (u_char *)vp;
822
823	p[0] = (u_char)(v >> 24) & 0xff;
824	p[1] = (u_char)(v >> 16) & 0xff;
825	p[2] = (u_char)(v >> 8) & 0xff;
826	p[3] = (u_char)v & 0xff;
827}
828
829
830void
831put_u16(void *vp, u_int16_t v)
832{
833	u_char *p = (u_char *)vp;
834
835	p[0] = (u_char)(v >> 8) & 0xff;
836	p[1] = (u_char)v & 0xff;
837}
838
839void
840ms_subtract_diff(struct timeval *start, int *ms)
841{
842	struct timeval diff, finish;
843
844	gettimeofday(&finish, NULL);
845	timersub(&finish, start, &diff);
846	*ms -= (diff.tv_sec * 1000) + (diff.tv_usec / 1000);
847}
848
849void
850ms_to_timeval(struct timeval *tv, int ms)
851{
852	if (ms < 0)
853		ms = 0;
854	tv->tv_sec = ms / 1000;
855	tv->tv_usec = (ms % 1000) * 1000;
856}
857
858void
859bandwidth_limit_init(struct bwlimit *bw, u_int64_t kbps, size_t buflen)
860{
861	bw->buflen = buflen;
862	bw->rate = kbps;
863	bw->thresh = bw->rate;
864	bw->lamt = 0;
865	timerclear(&bw->bwstart);
866	timerclear(&bw->bwend);
867}
868
869/* Callback from read/write loop to insert bandwidth-limiting delays */
870void
871bandwidth_limit(struct bwlimit *bw, size_t read_len)
872{
873	u_int64_t waitlen;
874	struct timespec ts, rm;
875
876	if (!timerisset(&bw->bwstart)) {
877		gettimeofday(&bw->bwstart, NULL);
878		return;
879	}
880
881	bw->lamt += read_len;
882	if (bw->lamt < bw->thresh)
883		return;
884
885	gettimeofday(&bw->bwend, NULL);
886	timersub(&bw->bwend, &bw->bwstart, &bw->bwend);
887	if (!timerisset(&bw->bwend))
888		return;
889
890	bw->lamt *= 8;
891	waitlen = (double)1000000L * bw->lamt / bw->rate;
892
893	bw->bwstart.tv_sec = waitlen / 1000000L;
894	bw->bwstart.tv_usec = waitlen % 1000000L;
895
896	if (timercmp(&bw->bwstart, &bw->bwend, >)) {
897		timersub(&bw->bwstart, &bw->bwend, &bw->bwend);
898
899		/* Adjust the wait time */
900		if (bw->bwend.tv_sec) {
901			bw->thresh /= 2;
902			if (bw->thresh < bw->buflen / 4)
903				bw->thresh = bw->buflen / 4;
904		} else if (bw->bwend.tv_usec < 10000) {
905			bw->thresh *= 2;
906			if (bw->thresh > bw->buflen * 8)
907				bw->thresh = bw->buflen * 8;
908		}
909
910		TIMEVAL_TO_TIMESPEC(&bw->bwend, &ts);
911		while (nanosleep(&ts, &rm) == -1) {
912			if (errno != EINTR)
913				break;
914			ts = rm;
915		}
916	}
917
918	bw->lamt = 0;
919	gettimeofday(&bw->bwstart, NULL);
920}
921
922/* Make a template filename for mk[sd]temp() */
923void
924mktemp_proto(char *s, size_t len)
925{
926	const char *tmpdir;
927	int r;
928
929	if ((tmpdir = getenv("TMPDIR")) != NULL) {
930		r = snprintf(s, len, "%s/ssh-XXXXXXXXXXXX", tmpdir);
931		if (r > 0 && (size_t)r < len)
932			return;
933	}
934	r = snprintf(s, len, "/tmp/ssh-XXXXXXXXXXXX");
935	if (r < 0 || (size_t)r >= len)
936		fatal("%s: template string too short", __func__);
937}
938
939static const struct {
940	const char *name;
941	int value;
942} ipqos[] = {
943	{ "af11", IPTOS_DSCP_AF11 },
944	{ "af12", IPTOS_DSCP_AF12 },
945	{ "af13", IPTOS_DSCP_AF13 },
946	{ "af14", IPTOS_DSCP_AF21 },
947	{ "af22", IPTOS_DSCP_AF22 },
948	{ "af23", IPTOS_DSCP_AF23 },
949	{ "af31", IPTOS_DSCP_AF31 },
950	{ "af32", IPTOS_DSCP_AF32 },
951	{ "af33", IPTOS_DSCP_AF33 },
952	{ "af41", IPTOS_DSCP_AF41 },
953	{ "af42", IPTOS_DSCP_AF42 },
954	{ "af43", IPTOS_DSCP_AF43 },
955	{ "cs0", IPTOS_DSCP_CS0 },
956	{ "cs1", IPTOS_DSCP_CS1 },
957	{ "cs2", IPTOS_DSCP_CS2 },
958	{ "cs3", IPTOS_DSCP_CS3 },
959	{ "cs4", IPTOS_DSCP_CS4 },
960	{ "cs5", IPTOS_DSCP_CS5 },
961	{ "cs6", IPTOS_DSCP_CS6 },
962	{ "cs7", IPTOS_DSCP_CS7 },
963	{ "ef", IPTOS_DSCP_EF },
964	{ "lowdelay", IPTOS_LOWDELAY },
965	{ "throughput", IPTOS_THROUGHPUT },
966	{ "reliability", IPTOS_RELIABILITY },
967	{ NULL, -1 }
968};
969
970int
971parse_ipqos(const char *cp)
972{
973	u_int i;
974	char *ep;
975	long val;
976
977	if (cp == NULL)
978		return -1;
979	for (i = 0; ipqos[i].name != NULL; i++) {
980		if (strcasecmp(cp, ipqos[i].name) == 0)
981			return ipqos[i].value;
982	}
983	/* Try parsing as an integer */
984	val = strtol(cp, &ep, 0);
985	if (*cp == '\0' || *ep != '\0' || val < 0 || val > 255)
986		return -1;
987	return val;
988}
989
990const char *
991iptos2str(int iptos)
992{
993	int i;
994	static char iptos_str[sizeof "0xff"];
995
996	for (i = 0; ipqos[i].name != NULL; i++) {
997		if (ipqos[i].value == iptos)
998			return ipqos[i].name;
999	}
1000	snprintf(iptos_str, sizeof iptos_str, "0x%02x", iptos);
1001	return iptos_str;
1002}
1003void
1004sock_set_v6only(int s)
1005{
1006#ifdef IPV6_V6ONLY
1007	int on = 1;
1008
1009	debug3("%s: set socket %d IPV6_V6ONLY", __func__, s);
1010	if (setsockopt(s, IPPROTO_IPV6, IPV6_V6ONLY, &on, sizeof(on)) == -1)
1011		error("setsockopt IPV6_V6ONLY: %s", strerror(errno));
1012#endif
1013}
1014