misc.c revision 294693 
1/* $OpenBSD: misc.c,v 1.92 2013/10/14 23:28:23 djm 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 <ctype.h>
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 && errno != 0)
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#ifdef HAVE_STRUCT_PASSWD_PW_GECOS
211	copy->pw_gecos = xstrdup(pw->pw_gecos);
212#endif
213	copy->pw_uid = pw->pw_uid;
214	copy->pw_gid = pw->pw_gid;
215#ifdef HAVE_STRUCT_PASSWD_PW_EXPIRE
216	copy->pw_expire = pw->pw_expire;
217#endif
218#ifdef HAVE_STRUCT_PASSWD_PW_CHANGE
219	copy->pw_change = pw->pw_change;
220#endif
221#ifdef HAVE_STRUCT_PASSWD_PW_CLASS
222	copy->pw_class = xstrdup(pw->pw_class);
223#endif
224	copy->pw_dir = xstrdup(pw->pw_dir);
225	copy->pw_shell = xstrdup(pw->pw_shell);
226	return copy;
227}
228
229/*
230 * Convert ASCII string to TCP/IP port number.
231 * Port must be >=0 and <=65535.
232 * Return -1 if invalid.
233 */
234int
235a2port(const char *s)
236{
237	long long port;
238	const char *errstr;
239
240	port = strtonum(s, 0, 65535, &errstr);
241	if (errstr != NULL)
242		return -1;
243	return (int)port;
244}
245
246int
247a2tun(const char *s, int *remote)
248{
249	const char *errstr = NULL;
250	char *sp, *ep;
251	int tun;
252
253	if (remote != NULL) {
254		*remote = SSH_TUNID_ANY;
255		sp = xstrdup(s);
256		if ((ep = strchr(sp, ':')) == NULL) {
257			free(sp);
258			return (a2tun(s, NULL));
259		}
260		ep[0] = '\0'; ep++;
261		*remote = a2tun(ep, NULL);
262		tun = a2tun(sp, NULL);
263		free(sp);
264		return (*remote == SSH_TUNID_ERR ? *remote : tun);
265	}
266
267	if (strcasecmp(s, "any") == 0)
268		return (SSH_TUNID_ANY);
269
270	tun = strtonum(s, 0, SSH_TUNID_MAX, &errstr);
271	if (errstr != NULL)
272		return (SSH_TUNID_ERR);
273
274	return (tun);
275}
276
277#define SECONDS		1
278#define MINUTES		(SECONDS * 60)
279#define HOURS		(MINUTES * 60)
280#define DAYS		(HOURS * 24)
281#define WEEKS		(DAYS * 7)
282
283/*
284 * Convert a time string into seconds; format is
285 * a sequence of:
286 *      time[qualifier]
287 *
288 * Valid time qualifiers are:
289 *      <none>  seconds
290 *      s|S     seconds
291 *      m|M     minutes
292 *      h|H     hours
293 *      d|D     days
294 *      w|W     weeks
295 *
296 * Examples:
297 *      90m     90 minutes
298 *      1h30m   90 minutes
299 *      2d      2 days
300 *      1w      1 week
301 *
302 * Return -1 if time string is invalid.
303 */
304long
305convtime(const char *s)
306{
307	long total, secs;
308	const char *p;
309	char *endp;
310
311	errno = 0;
312	total = 0;
313	p = s;
314
315	if (p == NULL || *p == '\0')
316		return -1;
317
318	while (*p) {
319		secs = strtol(p, &endp, 10);
320		if (p == endp ||
321		    (errno == ERANGE && (secs == LONG_MIN || secs == LONG_MAX)) ||
322		    secs < 0)
323			return -1;
324
325		switch (*endp++) {
326		case '\0':
327			endp--;
328			break;
329		case 's':
330		case 'S':
331			break;
332		case 'm':
333		case 'M':
334			secs *= MINUTES;
335			break;
336		case 'h':
337		case 'H':
338			secs *= HOURS;
339			break;
340		case 'd':
341		case 'D':
342			secs *= DAYS;
343			break;
344		case 'w':
345		case 'W':
346			secs *= WEEKS;
347			break;
348		default:
349			return -1;
350		}
351		total += secs;
352		if (total < 0)
353			return -1;
354		p = endp;
355	}
356
357	return total;
358}
359
360/*
361 * Returns a standardized host+port identifier string.
362 * Caller must free returned string.
363 */
364char *
365put_host_port(const char *host, u_short port)
366{
367	char *hoststr;
368
369	if (port == 0 || port == SSH_DEFAULT_PORT)
370		return(xstrdup(host));
371	if (asprintf(&hoststr, "[%s]:%d", host, (int)port) < 0)
372		fatal("put_host_port: asprintf: %s", strerror(errno));
373	debug3("put_host_port: %s", hoststr);
374	return hoststr;
375}
376
377/*
378 * Search for next delimiter between hostnames/addresses and ports.
379 * Argument may be modified (for termination).
380 * Returns *cp if parsing succeeds.
381 * *cp is set to the start of the next delimiter, if one was found.
382 * If this is the last field, *cp is set to NULL.
383 */
384char *
385hpdelim(char **cp)
386{
387	char *s, *old;
388
389	if (cp == NULL || *cp == NULL)
390		return NULL;
391
392	old = s = *cp;
393	if (*s == '[') {
394		if ((s = strchr(s, ']')) == NULL)
395			return NULL;
396		else
397			s++;
398	} else if ((s = strpbrk(s, ":/")) == NULL)
399		s = *cp + strlen(*cp); /* skip to end (see first case below) */
400
401	switch (*s) {
402	case '\0':
403		*cp = NULL;	/* no more fields*/
404		break;
405
406	case ':':
407	case '/':
408		*s = '\0';	/* terminate */
409		*cp = s + 1;
410		break;
411
412	default:
413		return NULL;
414	}
415
416	return old;
417}
418
419char *
420cleanhostname(char *host)
421{
422	if (*host == '[' && host[strlen(host) - 1] == ']') {
423		host[strlen(host) - 1] = '\0';
424		return (host + 1);
425	} else
426		return host;
427}
428
429char *
430colon(char *cp)
431{
432	int flag = 0;
433
434	if (*cp == ':')		/* Leading colon is part of file name. */
435		return NULL;
436	if (*cp == '[')
437		flag = 1;
438
439	for (; *cp; ++cp) {
440		if (*cp == '@' && *(cp+1) == '[')
441			flag = 1;
442		if (*cp == ']' && *(cp+1) == ':' && flag)
443			return (cp+1);
444		if (*cp == ':' && !flag)
445			return (cp);
446		if (*cp == '/')
447			return NULL;
448	}
449	return NULL;
450}
451
452/* function to assist building execv() arguments */
453void
454addargs(arglist *args, char *fmt, ...)
455{
456	va_list ap;
457	char *cp;
458	u_int nalloc;
459	int r;
460
461	va_start(ap, fmt);
462	r = vasprintf(&cp, fmt, ap);
463	va_end(ap);
464	if (r == -1)
465		fatal("addargs: argument too long");
466
467	nalloc = args->nalloc;
468	if (args->list == NULL) {
469		nalloc = 32;
470		args->num = 0;
471	} else if (args->num+2 >= nalloc)
472		nalloc *= 2;
473
474	args->list = xrealloc(args->list, nalloc, sizeof(char *));
475	args->nalloc = nalloc;
476	args->list[args->num++] = cp;
477	args->list[args->num] = NULL;
478}
479
480void
481replacearg(arglist *args, u_int which, char *fmt, ...)
482{
483	va_list ap;
484	char *cp;
485	int r;
486
487	va_start(ap, fmt);
488	r = vasprintf(&cp, fmt, ap);
489	va_end(ap);
490	if (r == -1)
491		fatal("replacearg: argument too long");
492
493	if (which >= args->num)
494		fatal("replacearg: tried to replace invalid arg %d >= %d",
495		    which, args->num);
496	free(args->list[which]);
497	args->list[which] = cp;
498}
499
500void
501freeargs(arglist *args)
502{
503	u_int i;
504
505	if (args->list != NULL) {
506		for (i = 0; i < args->num; i++)
507			free(args->list[i]);
508		free(args->list);
509		args->nalloc = args->num = 0;
510		args->list = NULL;
511	}
512}
513
514/*
515 * Expands tildes in the file name.  Returns data allocated by xmalloc.
516 * Warning: this calls getpw*.
517 */
518char *
519tilde_expand_filename(const char *filename, uid_t uid)
520{
521	const char *path, *sep;
522	char user[128], *ret;
523	struct passwd *pw;
524	u_int len, slash;
525
526	if (*filename != '~')
527		return (xstrdup(filename));
528	filename++;
529
530	path = strchr(filename, '/');
531	if (path != NULL && path > filename) {		/* ~user/path */
532		slash = path - filename;
533		if (slash > sizeof(user) - 1)
534			fatal("tilde_expand_filename: ~username too long");
535		memcpy(user, filename, slash);
536		user[slash] = '\0';
537		if ((pw = getpwnam(user)) == NULL)
538			fatal("tilde_expand_filename: No such user %s", user);
539	} else if ((pw = getpwuid(uid)) == NULL)	/* ~/path */
540		fatal("tilde_expand_filename: No such uid %ld", (long)uid);
541
542	/* Make sure directory has a trailing '/' */
543	len = strlen(pw->pw_dir);
544	if (len == 0 || pw->pw_dir[len - 1] != '/')
545		sep = "/";
546	else
547		sep = "";
548
549	/* Skip leading '/' from specified path */
550	if (path != NULL)
551		filename = path + 1;
552
553	if (xasprintf(&ret, "%s%s%s", pw->pw_dir, sep, filename) >= MAXPATHLEN)
554		fatal("tilde_expand_filename: Path too long");
555
556	return (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
858time_t
859monotime(void)
860{
861#if defined(HAVE_CLOCK_GETTIME) && defined(CLOCK_MONOTONIC)
862	struct timespec ts;
863	static int gettime_failed = 0;
864
865	if (!gettime_failed) {
866		if (clock_gettime(CLOCK_MONOTONIC, &ts) == 0)
867			return (ts.tv_sec);
868		debug3("clock_gettime: %s", strerror(errno));
869		gettime_failed = 1;
870	}
871#endif
872
873	return time(NULL);
874}
875
876void
877bandwidth_limit_init(struct bwlimit *bw, u_int64_t kbps, size_t buflen)
878{
879	bw->buflen = buflen;
880	bw->rate = kbps;
881	bw->thresh = bw->rate;
882	bw->lamt = 0;
883	timerclear(&bw->bwstart);
884	timerclear(&bw->bwend);
885}
886
887/* Callback from read/write loop to insert bandwidth-limiting delays */
888void
889bandwidth_limit(struct bwlimit *bw, size_t read_len)
890{
891	u_int64_t waitlen;
892	struct timespec ts, rm;
893
894	if (!timerisset(&bw->bwstart)) {
895		gettimeofday(&bw->bwstart, NULL);
896		return;
897	}
898
899	bw->lamt += read_len;
900	if (bw->lamt < bw->thresh)
901		return;
902
903	gettimeofday(&bw->bwend, NULL);
904	timersub(&bw->bwend, &bw->bwstart, &bw->bwend);
905	if (!timerisset(&bw->bwend))
906		return;
907
908	bw->lamt *= 8;
909	waitlen = (double)1000000L * bw->lamt / bw->rate;
910
911	bw->bwstart.tv_sec = waitlen / 1000000L;
912	bw->bwstart.tv_usec = waitlen % 1000000L;
913
914	if (timercmp(&bw->bwstart, &bw->bwend, >)) {
915		timersub(&bw->bwstart, &bw->bwend, &bw->bwend);
916
917		/* Adjust the wait time */
918		if (bw->bwend.tv_sec) {
919			bw->thresh /= 2;
920			if (bw->thresh < bw->buflen / 4)
921				bw->thresh = bw->buflen / 4;
922		} else if (bw->bwend.tv_usec < 10000) {
923			bw->thresh *= 2;
924			if (bw->thresh > bw->buflen * 8)
925				bw->thresh = bw->buflen * 8;
926		}
927
928		TIMEVAL_TO_TIMESPEC(&bw->bwend, &ts);
929		while (nanosleep(&ts, &rm) == -1) {
930			if (errno != EINTR)
931				break;
932			ts = rm;
933		}
934	}
935
936	bw->lamt = 0;
937	gettimeofday(&bw->bwstart, NULL);
938}
939
940/* Make a template filename for mk[sd]temp() */
941void
942mktemp_proto(char *s, size_t len)
943{
944	const char *tmpdir;
945	int r;
946
947	if ((tmpdir = getenv("TMPDIR")) != NULL) {
948		r = snprintf(s, len, "%s/ssh-XXXXXXXXXXXX", tmpdir);
949		if (r > 0 && (size_t)r < len)
950			return;
951	}
952	r = snprintf(s, len, "/tmp/ssh-XXXXXXXXXXXX");
953	if (r < 0 || (size_t)r >= len)
954		fatal("%s: template string too short", __func__);
955}
956
957static const struct {
958	const char *name;
959	int value;
960} ipqos[] = {
961	{ "af11", IPTOS_DSCP_AF11 },
962	{ "af12", IPTOS_DSCP_AF12 },
963	{ "af13", IPTOS_DSCP_AF13 },
964	{ "af21", IPTOS_DSCP_AF21 },
965	{ "af22", IPTOS_DSCP_AF22 },
966	{ "af23", IPTOS_DSCP_AF23 },
967	{ "af31", IPTOS_DSCP_AF31 },
968	{ "af32", IPTOS_DSCP_AF32 },
969	{ "af33", IPTOS_DSCP_AF33 },
970	{ "af41", IPTOS_DSCP_AF41 },
971	{ "af42", IPTOS_DSCP_AF42 },
972	{ "af43", IPTOS_DSCP_AF43 },
973	{ "cs0", IPTOS_DSCP_CS0 },
974	{ "cs1", IPTOS_DSCP_CS1 },
975	{ "cs2", IPTOS_DSCP_CS2 },
976	{ "cs3", IPTOS_DSCP_CS3 },
977	{ "cs4", IPTOS_DSCP_CS4 },
978	{ "cs5", IPTOS_DSCP_CS5 },
979	{ "cs6", IPTOS_DSCP_CS6 },
980	{ "cs7", IPTOS_DSCP_CS7 },
981	{ "ef", IPTOS_DSCP_EF },
982	{ "lowdelay", IPTOS_LOWDELAY },
983	{ "throughput", IPTOS_THROUGHPUT },
984	{ "reliability", IPTOS_RELIABILITY },
985	{ NULL, -1 }
986};
987
988int
989parse_ipqos(const char *cp)
990{
991	u_int i;
992	char *ep;
993	long val;
994
995	if (cp == NULL)
996		return -1;
997	for (i = 0; ipqos[i].name != NULL; i++) {
998		if (strcasecmp(cp, ipqos[i].name) == 0)
999			return ipqos[i].value;
1000	}
1001	/* Try parsing as an integer */
1002	val = strtol(cp, &ep, 0);
1003	if (*cp == '\0' || *ep != '\0' || val < 0 || val > 255)
1004		return -1;
1005	return val;
1006}
1007
1008const char *
1009iptos2str(int iptos)
1010{
1011	int i;
1012	static char iptos_str[sizeof "0xff"];
1013
1014	for (i = 0; ipqos[i].name != NULL; i++) {
1015		if (ipqos[i].value == iptos)
1016			return ipqos[i].name;
1017	}
1018	snprintf(iptos_str, sizeof iptos_str, "0x%02x", iptos);
1019	return iptos_str;
1020}
1021
1022void
1023lowercase(char *s)
1024{
1025	for (; *s; s++)
1026		*s = tolower((u_char)*s);
1027}
1028void
1029sock_set_v6only(int s)
1030{
1031#ifdef IPV6_V6ONLY
1032	int on = 1;
1033
1034	debug3("%s: set socket %d IPV6_V6ONLY", __func__, s);
1035	if (setsockopt(s, IPPROTO_IPV6, IPV6_V6ONLY, &on, sizeof(on)) == -1)
1036		error("setsockopt IPV6_V6ONLY: %s", strerror(errno));
1037#endif
1038}
1039