[openssh.git] / misc.c

/*
 * Copyright (c) 2000 Markus Friedl.  All rights reserved.
 * Copyright (c) 2005 Damien Miller.  All rights reserved.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions
 * are met:
 * 1. Redistributions of source code must retain the above copyright
 *    notice, this list of conditions and the following disclaimer.
 * 2. Redistributions in binary form must reproduce the above copyright
 *    notice, this list of conditions and the following disclaimer in the
 *    documentation and/or other materials provided with the distribution.
 *
 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
 * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
 * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
 * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
 * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
 * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
 * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
 */

#include "includes.h"
RCSID("$OpenBSD: misc.c,v 1.37 2005/12/08 18:34:11 reyk Exp $");

#include "misc.h"
#include "log.h"
#include "xmalloc.h"

/* remove newline at end of string */
char *
chop(char *s)
{
	char *t = s;
	while (*t) {
		if (*t == '\n' || *t == '\r') {
			*t = '\0';
			return s;
		}
		t++;
	}
	return s;

}

/* set/unset filedescriptor to non-blocking */
int
set_nonblock(int fd)
{
	int val;

	val = fcntl(fd, F_GETFL, 0);
	if (val < 0) {
		error("fcntl(%d, F_GETFL, 0): %s", fd, strerror(errno));
		return (-1);
	}
	if (val & O_NONBLOCK) {
		debug3("fd %d is O_NONBLOCK", fd);
		return (0);
	}
	debug2("fd %d setting O_NONBLOCK", fd);
	val |= O_NONBLOCK;
	if (fcntl(fd, F_SETFL, val) == -1) {
		debug("fcntl(%d, F_SETFL, O_NONBLOCK): %s", fd,
		    strerror(errno));
		return (-1);
	}
	return (0);
}

int
unset_nonblock(int fd)
{
	int val;

	val = fcntl(fd, F_GETFL, 0);
	if (val < 0) {
		error("fcntl(%d, F_GETFL, 0): %s", fd, strerror(errno));
		return (-1);
	}
	if (!(val & O_NONBLOCK)) {
		debug3("fd %d is not O_NONBLOCK", fd);
		return (0);
	}
	debug("fd %d clearing O_NONBLOCK", fd);
	val &= ~O_NONBLOCK;
	if (fcntl(fd, F_SETFL, val) == -1) {
		debug("fcntl(%d, F_SETFL, ~O_NONBLOCK): %s",
		    fd, strerror(errno));
		return (-1);
	}
	return (0);
}

/* disable nagle on socket */
void
set_nodelay(int fd)
{
	int opt;
	socklen_t optlen;

	optlen = sizeof opt;
	if (getsockopt(fd, IPPROTO_TCP, TCP_NODELAY, &opt, &optlen) == -1) {
		debug("getsockopt TCP_NODELAY: %.100s", strerror(errno));
		return;
	}
	if (opt == 1) {
		debug2("fd %d is TCP_NODELAY", fd);
		return;
	}
	opt = 1;
	debug2("fd %d setting TCP_NODELAY", fd);
	if (setsockopt(fd, IPPROTO_TCP, TCP_NODELAY, &opt, sizeof opt) == -1)
		error("setsockopt TCP_NODELAY: %.100s", strerror(errno));
}

/* Characters considered whitespace in strsep calls. */
#define WHITESPACE " \t\r\n"

/* return next token in configuration line */
char *
strdelim(char **s)
{
	char *old;
	int wspace = 0;

	if (*s == NULL)
		return NULL;

	old = *s;

	*s = strpbrk(*s, WHITESPACE "=");
	if (*s == NULL)
		return (old);

	/* Allow only one '=' to be skipped */
	if (*s[0] == '=')
		wspace = 1;
	*s[0] = '\0';

	*s += strspn(*s + 1, WHITESPACE) + 1;
	if (*s[0] == '=' && !wspace)
		*s += strspn(*s + 1, WHITESPACE) + 1;

	return (old);
}

struct passwd *
pwcopy(struct passwd *pw)
{
	struct passwd *copy = xmalloc(sizeof(*copy));

	memset(copy, 0, sizeof(*copy));
	copy->pw_name = xstrdup(pw->pw_name);
	copy->pw_passwd = xstrdup(pw->pw_passwd);
	copy->pw_gecos = xstrdup(pw->pw_gecos);
	copy->pw_uid = pw->pw_uid;
	copy->pw_gid = pw->pw_gid;
#ifdef HAVE_PW_EXPIRE_IN_PASSWD
	copy->pw_expire = pw->pw_expire;
#endif
#ifdef HAVE_PW_CHANGE_IN_PASSWD
	copy->pw_change = pw->pw_change;
#endif
#ifdef HAVE_PW_CLASS_IN_PASSWD
	copy->pw_class = xstrdup(pw->pw_class);
#endif
	copy->pw_dir = xstrdup(pw->pw_dir);
	copy->pw_shell = xstrdup(pw->pw_shell);
	return copy;
}

/*
 * Convert ASCII string to TCP/IP port number.
 * Port must be >0 and <=65535.
 * Return 0 if invalid.
 */
int
a2port(const char *s)
{
	long port;
	char *endp;

	errno = 0;
	port = strtol(s, &endp, 0);
	if (s == endp || *endp != '\0' ||
	    (errno == ERANGE && (port == LONG_MIN || port == LONG_MAX)) ||
	    port <= 0 || port > 65535)
		return 0;

	return port;
}

int
a2tun(const char *s, int *remote)
{
	const char *errstr = NULL;
	char *sp, *ep;
	int tun;

	if (remote != NULL) {
		*remote = SSH_TUNID_ANY;
		sp = xstrdup(s);
		if ((ep = strchr(sp, ':')) == NULL) {
			xfree(sp);
			return (a2tun(s, NULL));
		}
		ep[0] = '\0'; ep++;
		*remote = a2tun(ep, NULL);
		tun = a2tun(sp, NULL);
		xfree(sp);
		return (*remote == SSH_TUNID_ERR ? *remote : tun);
	}

	if (strcasecmp(s, "any") == 0)
		return (SSH_TUNID_ANY);

	tun = strtonum(s, 0, SSH_TUNID_MAX, &errstr);
	if (errstr != NULL)
		return (SSH_TUNID_ERR);

	return (tun);
}

#define SECONDS		1
#define MINUTES		(SECONDS * 60)
#define HOURS		(MINUTES * 60)
#define DAYS		(HOURS * 24)
#define WEEKS		(DAYS * 7)

/*
 * Convert a time string into seconds; format is
 * a sequence of:
 *      time[qualifier]
 *
 * Valid time qualifiers are:
 *      <none>  seconds
 *      s|S     seconds
 *      m|M     minutes
 *      h|H     hours
 *      d|D     days
 *      w|W     weeks
 *
 * Examples:
 *      90m     90 minutes
 *      1h30m   90 minutes
 *      2d      2 days
 *      1w      1 week
 *
 * Return -1 if time string is invalid.
 */
long
convtime(const char *s)
{
	long total, secs;
	const char *p;
	char *endp;

	errno = 0;
	total = 0;
	p = s;

	if (p == NULL || *p == '\0')
		return -1;

	while (*p) {
		secs = strtol(p, &endp, 10);
		if (p == endp ||
		    (errno == ERANGE && (secs == LONG_MIN || secs == LONG_MAX)) ||
		    secs < 0)
			return -1;

		switch (*endp++) {
		case '\0':
			endp--;
		case 's':
		case 'S':
			break;
		case 'm':
		case 'M':
			secs *= MINUTES;
			break;
		case 'h':
		case 'H':
			secs *= HOURS;
			break;
		case 'd':
		case 'D':
			secs *= DAYS;
			break;
		case 'w':
		case 'W':
			secs *= WEEKS;
			break;
		default:
			return -1;
		}
		total += secs;
		if (total < 0)
			return -1;
		p = endp;
	}

	return total;
}

/*
 * Search for next delimiter between hostnames/addresses and ports.
 * Argument may be modified (for termination).
 * Returns *cp if parsing succeeds.
 * *cp is set to the start of the next delimiter, if one was found.
 * If this is the last field, *cp is set to NULL.
 */
char *
hpdelim(char **cp)
{
	char *s, *old;

	if (cp == NULL || *cp == NULL)
		return NULL;

	old = s = *cp;
	if (*s == '[') {
		if ((s = strchr(s, ']')) == NULL)
			return NULL;
		else
			s++;
	} else if ((s = strpbrk(s, ":/")) == NULL)
		s = *cp + strlen(*cp); /* skip to end (see first case below) */

	switch (*s) {
	case '\0':
		*cp = NULL;	/* no more fields*/
		break;

	case ':':
	case '/':
		*s = '\0';	/* terminate */
		*cp = s + 1;
		break;

	default:
		return NULL;
	}

	return old;
}

char *
cleanhostname(char *host)
{
	if (*host == '[' && host[strlen(host) - 1] == ']') {
		host[strlen(host) - 1] = '\0';
		return (host + 1);
	} else
		return host;
}

char *
colon(char *cp)
{
	int flag = 0;

	if (*cp == ':')		/* Leading colon is part of file name. */
		return (0);
	if (*cp == '[')
		flag = 1;

	for (; *cp; ++cp) {
		if (*cp == '@' && *(cp+1) == '[')
			flag = 1;
		if (*cp == ']' && *(cp+1) == ':' && flag)
			return (cp+1);
		if (*cp == ':' && !flag)
			return (cp);
		if (*cp == '/')
			return (0);
	}
	return (0);
}

/* function to assist building execv() arguments */
void
addargs(arglist *args, char *fmt, ...)
{
	va_list ap;
	char buf[1024];
	u_int nalloc;

	va_start(ap, fmt);
	vsnprintf(buf, sizeof(buf), fmt, ap);
	va_end(ap);

	nalloc = args->nalloc;
	if (args->list == NULL) {
		nalloc = 32;
		args->num = 0;
	} else if (args->num+2 >= nalloc)
		nalloc *= 2;

	args->list = xrealloc(args->list, nalloc * sizeof(char *));
	args->nalloc = nalloc;
	args->list[args->num++] = xstrdup(buf);
	args->list[args->num] = NULL;
}

/*
 * Expands tildes in the file name.  Returns data allocated by xmalloc.
 * Warning: this calls getpw*.
 */
char *
tilde_expand_filename(const char *filename, uid_t uid)
{
	const char *path;
	char user[128], ret[MAXPATHLEN];
	struct passwd *pw;
	u_int len, slash;

	if (*filename != '~')
		return (xstrdup(filename));
	filename++;

	path = strchr(filename, '/');
	if (path != NULL && path > filename) {		/* ~user/path */
		slash = path - filename;
		if (slash > sizeof(user) - 1)
			fatal("tilde_expand_filename: ~username too long");
		memcpy(user, filename, slash);
		user[slash] = '\0';
		if ((pw = getpwnam(user)) == NULL)
			fatal("tilde_expand_filename: No such user %s", user);
	} else if ((pw = getpwuid(uid)) == NULL)	/* ~/path */
		fatal("tilde_expand_filename: No such uid %d", uid);

	if (strlcpy(ret, pw->pw_dir, sizeof(ret)) >= sizeof(ret))
		fatal("tilde_expand_filename: Path too long");

	/* Make sure directory has a trailing '/' */
	len = strlen(pw->pw_dir);
	if ((len == 0 || pw->pw_dir[len - 1] != '/') &&
	    strlcat(ret, "/", sizeof(ret)) >= sizeof(ret))
		fatal("tilde_expand_filename: Path too long");

	/* Skip leading '/' from specified path */
	if (path != NULL)
		filename = path + 1;
	if (strlcat(ret, filename, sizeof(ret)) >= sizeof(ret))
		fatal("tilde_expand_filename: Path too long");

	return (xstrdup(ret));
}

/*
 * Expand a string with a set of %[char] escapes. A number of escapes may be
 * specified as (char *escape_chars, char *replacement) pairs. The list must
 * be terminated by a NULL escape_char. Returns replaced string in memory
 * allocated by xmalloc.
 */
char *
percent_expand(const char *string, ...)
{
#define EXPAND_MAX_KEYS	16
	struct {
		const char *key;
		const char *repl;
	} keys[EXPAND_MAX_KEYS];
	u_int num_keys, i, j;
	char buf[4096];
	va_list ap;

	/* Gather keys */
	va_start(ap, string);
	for (num_keys = 0; num_keys < EXPAND_MAX_KEYS; num_keys++) {
		keys[num_keys].key = va_arg(ap, char *);
		if (keys[num_keys].key == NULL)
			break;
		keys[num_keys].repl = va_arg(ap, char *);
		if (keys[num_keys].repl == NULL)
			fatal("percent_expand: NULL replacement");
	}
	va_end(ap);

	if (num_keys >= EXPAND_MAX_KEYS)
		fatal("percent_expand: too many keys");

	/* Expand string */
	*buf = '\0';
	for (i = 0; *string != '\0'; string++) {
		if (*string != '%') {
 append:
			buf[i++] = *string;
			if (i >= sizeof(buf))
				fatal("percent_expand: string too long");
			buf[i] = '\0';
			continue;
		}
		string++;
		if (*string == '%')
			goto append;
		for (j = 0; j < num_keys; j++) {
			if (strchr(keys[j].key, *string) != NULL) {
				i = strlcat(buf, keys[j].repl, sizeof(buf));
				if (i >= sizeof(buf))
					fatal("percent_expand: string too long");
				break;
			}
		}
		if (j >= num_keys)
			fatal("percent_expand: unknown key %%%c", *string);
	}
	return (xstrdup(buf));
#undef EXPAND_MAX_KEYS
}

/*
 * Read an entire line from a public key file into a static buffer, discarding
 * lines that exceed the buffer size.  Returns 0 on success, -1 on failure.
 */
int
read_keyfile_line(FILE *f, const char *filename, char *buf, size_t bufsz,
   u_long *lineno)
{
	while (fgets(buf, bufsz, f) != NULL) {
		(*lineno)++;
		if (buf[strlen(buf) - 1] == '\n' || feof(f)) {
			return 0;
		} else {
			debug("%s: %s line %lu exceeds size limit", __func__,
			    filename, *lineno);
			/* discard remainder of line */
			while (fgetc(f) != '\n' && !feof(f))
				;	/* nothing */
		}
	}
	return -1;
}

int
tun_open(int tun, int mode)
{
#if defined(CUSTOM_SYS_TUN_OPEN)
	return (sys_tun_open(tun, mode));
#elif defined(SSH_TUN_BSD)
	struct ifreq ifr;
	char name[100];
	int fd = -1, sock;

	/* Open the tunnel device */
	if (tun <= SSH_TUNID_MAX) {
		snprintf(name, sizeof(name), "/dev/tun%d", tun);
		fd = open(name, O_RDWR);
	} else if (tun == SSH_TUNID_ANY) {
		for (tun = 100; tun >= 0; tun--) {
			snprintf(name, sizeof(name), "/dev/tun%d", tun);
			if ((fd = open(name, O_RDWR)) >= 0)
				break;
		}
	} else {
		debug("%s: invalid tunnel %u\n", __func__, tun);
		return (-1);
	}

	if (fd < 0) {
		debug("%s: %s open failed: %s", __func__, name, strerror(errno));
		return (-1);
	}

	debug("%s: %s mode %d fd %d", __func__, name, mode, fd);

	/* Set the tunnel device operation mode */
	snprintf(ifr.ifr_name, sizeof(ifr.ifr_name), "tun%d", tun);
	if ((sock = socket(PF_UNIX, SOCK_STREAM, 0)) == -1)
		goto failed;

	if (ioctl(sock, SIOCGIFFLAGS, &ifr) == -1)
		goto failed;
	if (mode == SSH_TUNMODE_ETHERNET) {
		ifr.ifr_flags |= IFF_LINK0;
		if (ioctl(sock, SIOCSIFFLAGS, &ifr) == -1)
			goto failed;
	}
	ifr.ifr_flags |= IFF_UP;
	if (ioctl(sock, SIOCSIFFLAGS, &ifr) == -1)
		goto failed;

	close(sock);
	return (fd);

 failed:
	if (fd >= 0)
		close(fd);
	if (sock >= 0)
		close(sock);
	debug("%s: failed to set %s mode %d: %s", __func__, name,
	    mode, strerror(errno));
	return (-1);
#else
	error("Tunnel interfaces are not supported on this platform");
	return (-1);
#endif
}

void
sanitise_stdfd(void)
{
	int nullfd;

	if ((nullfd = open(_PATH_DEVNULL, O_RDWR)) == -1) {
		fprintf(stderr, "Couldn't open /dev/null: %s", strerror(errno));
		exit(1);
	}
	while (nullfd < 2) {
		if (dup2(nullfd, nullfd + 1) == -1) {
			fprintf(stderr, "dup2: %s", strerror(errno));
			exit(1);
		}
		nullfd++;
	}
	if (nullfd > 2)
		close(nullfd);
}

char *
tohex(const u_char *d, u_int l)
{
	char b[3], *r;
	u_int i, hl;

	hl = l * 2 + 1;
	r = xmalloc(hl);
	*r = '\0';
	for (i = 0; i < l; i++) {
		snprintf(b, sizeof(b), "%02x", d[i]);
		strlcat(r, b, hl);
	}
	return (r);
}
Commit	Line	Data
bcbf86ec	1	/*
bcbf86ec	2	* Copyright (c) 2000 Markus Friedl. All rights reserved.
a980cbd7	3	* Copyright (c) 2005 Damien Miller. All rights reserved.
bcbf86ec	4	*
	5	* Redistribution and use in source and binary forms, with or without
	6	* modification, are permitted provided that the following conditions
	7	* are met:
	8	* 1. Redistributions of source code must retain the above copyright
	9	* notice, this list of conditions and the following disclaimer.
	10	* 2. Redistributions in binary form must reproduce the above copyright
	11	* notice, this list of conditions and the following disclaimer in the
	12	* documentation and/or other materials provided with the distribution.
	13	*
	14	* THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
	15	* IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
	16	* OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
	17	* IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
	18	* INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
	19	* NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
	20	* DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
	21	* THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
	22	* (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
	23	* THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
	24	*/
	25
6d24277f	26	#include "includes.h"
a4f24bf8	27	RCSID("$OpenBSD: misc.c,v 1.37 2005/12/08 18:34:11 reyk Exp $");
6d24277f	28
1aa00dcb	29	#include "misc.h"
42f11eb2	30	#include "log.h"
4ab21f86	31	#include "xmalloc.h"
6d24277f	32
255cabd9	33	/* remove newline at end of string */
6d24277f	34	char *
	35	chop(char *s)
	36	{
	37	char *t = s;
	38	while (*t) {
6aacefa7	39	if (t == '\n' \|\| t == '\r') {
6d24277f	40	*t = '\0';
	41	return s;
	42	}
	43	t++;
	44	}
	45	return s;
	46
	47	}
	48
255cabd9	49	/* set/unset filedescriptor to non-blocking */
170694d7	50	int
6d24277f	51	set_nonblock(int fd)
	52	{
	53	int val;
89aa792b	54
6d24277f	55	val = fcntl(fd, F_GETFL, 0);
	56	if (val < 0) {
	57	error("fcntl(%d, F_GETFL, 0): %s", fd, strerror(errno));
170694d7	58	return (-1);
6d24277f	59	}
a22aff1f	60	if (val & O_NONBLOCK) {
170694d7	61	debug3("fd %d is O_NONBLOCK", fd);
170694d7	62	return (0);
a22aff1f	63	}
45c42d58	64	debug2("fd %d setting O_NONBLOCK", fd);
6d24277f	65	val \|= O_NONBLOCK;
170694d7	66	if (fcntl(fd, F_SETFL, val) == -1) {
	67	debug("fcntl(%d, F_SETFL, O_NONBLOCK): %s", fd,
	68	strerror(errno));
	69	return (-1);
	70	}
	71	return (0);
6d24277f	72	}
6d24277f	73
170694d7	74	int
89aa792b	75	unset_nonblock(int fd)
	76	{
	77	int val;
	78
	79	val = fcntl(fd, F_GETFL, 0);
	80	if (val < 0) {
	81	error("fcntl(%d, F_GETFL, 0): %s", fd, strerror(errno));
170694d7	82	return (-1);
89aa792b	83	}
89aa792b	84	if (!(val & O_NONBLOCK)) {
170694d7	85	debug3("fd %d is not O_NONBLOCK", fd);
170694d7	86	return (0);
89aa792b	87	}
e04e7a19	88	debug("fd %d clearing O_NONBLOCK", fd);
89aa792b	89	val &= ~O_NONBLOCK;
170694d7	90	if (fcntl(fd, F_SETFL, val) == -1) {
170694d7	91	debug("fcntl(%d, F_SETFL, ~O_NONBLOCK): %s",
c92ec40b	92	fd, strerror(errno));
170694d7	93	return (-1);
	94	}
	95	return (0);
89aa792b	96	}
89aa792b	97
bcc0381e	98	/* disable nagle on socket */
	99	void
	100	set_nodelay(int fd)
	101	{
3c05447a	102	int opt;
3c05447a	103	socklen_t optlen;
bcc0381e	104
811a6342	105	optlen = sizeof opt;
811a6342	106	if (getsockopt(fd, IPPROTO_TCP, TCP_NODELAY, &opt, &optlen) == -1) {
f7fb35fe	107	debug("getsockopt TCP_NODELAY: %.100s", strerror(errno));
811a6342	108	return;
	109	}
	110	if (opt == 1) {
	111	debug2("fd %d is TCP_NODELAY", fd);
	112	return;
	113	}
	114	opt = 1;
6226a8f8	115	debug2("fd %d setting TCP_NODELAY", fd);
811a6342	116	if (setsockopt(fd, IPPROTO_TCP, TCP_NODELAY, &opt, sizeof opt) == -1)
bcc0381e	117	error("setsockopt TCP_NODELAY: %.100s", strerror(errno));
	118	}
	119
6d24277f	120	/* Characters considered whitespace in strsep calls. */
	121	#define WHITESPACE " \t\r\n"
	122
255cabd9	123	/* return next token in configuration line */
6d24277f	124	char *
	125	strdelim(char **s)
	126	{
	127	char *old;
	128	int wspace = 0;
	129
	130	if (*s == NULL)
	131	return NULL;
	132
	133	old = *s;
	134
	135	s = strpbrk(s, WHITESPACE "=");
	136	if (*s == NULL)
	137	return (old);
	138
	139	/* Allow only one '=' to be skipped */
	140	if (*s[0] == '=')
	141	wspace = 1;
	142	*s[0] = '\0';
	143
	144	s += strspn(s + 1, WHITESPACE) + 1;
	145	if (*s[0] == '=' && !wspace)
	146	s += strspn(s + 1, WHITESPACE) + 1;
	147
	148	return (old);
	149	}
1aa00dcb	150
3b1a83df	151	struct passwd *
	152	pwcopy(struct passwd *pw)
	153	{
	154	struct passwd copy = xmalloc(sizeof(copy));
5649fbbe	155
3b1a83df	156	memset(copy, 0, sizeof(*copy));
	157	copy->pw_name = xstrdup(pw->pw_name);
	158	copy->pw_passwd = xstrdup(pw->pw_passwd);
5649fbbe	159	copy->pw_gecos = xstrdup(pw->pw_gecos);
3b1a83df	160	copy->pw_uid = pw->pw_uid;
3b1a83df	161	copy->pw_gid = pw->pw_gid;
7751d4eb	162	#ifdef HAVE_PW_EXPIRE_IN_PASSWD
c4d49b85	163	copy->pw_expire = pw->pw_expire;
7751d4eb	164	#endif
7751d4eb	165	#ifdef HAVE_PW_CHANGE_IN_PASSWD
c4d49b85	166	copy->pw_change = pw->pw_change;
7751d4eb	167	#endif
2605addd	168	#ifdef HAVE_PW_CLASS_IN_PASSWD
3b1a83df	169	copy->pw_class = xstrdup(pw->pw_class);
2605addd	170	#endif
3b1a83df	171	copy->pw_dir = xstrdup(pw->pw_dir);
	172	copy->pw_shell = xstrdup(pw->pw_shell);
	173	return copy;
	174	}
	175
255cabd9	176	/*
	177	* Convert ASCII string to TCP/IP port number.
	178	* Port must be >0 and <=65535.
	179	* Return 0 if invalid.
	180	*/
	181	int
	182	a2port(const char *s)
2d2a2c65	183	{
	184	long port;
	185	char *endp;
	186
	187	errno = 0;
	188	port = strtol(s, &endp, 0);
	189	if (s == endp \|\| *endp != '\0' \|\|
	190	(errno == ERANGE && (port == LONG_MIN \|\| port == LONG_MAX)) \|\|
	191	port <= 0 \|\| port > 65535)
	192	return 0;
	193
	194	return port;
	195	}
	196
d20f3c9e	197	int
	198	a2tun(const char s, int remote)
	199	{
	200	const char *errstr = NULL;
	201	char sp, ep;
	202	int tun;
	203
	204	if (remote != NULL) {
a4f24bf8	205	*remote = SSH_TUNID_ANY;
d20f3c9e	206	sp = xstrdup(s);
	207	if ((ep = strchr(sp, ':')) == NULL) {
	208	xfree(sp);
	209	return (a2tun(s, NULL));
	210	}
	211	ep[0] = '\0'; ep++;
	212	*remote = a2tun(ep, NULL);
	213	tun = a2tun(sp, NULL);
	214	xfree(sp);
a4f24bf8	215	return (remote == SSH_TUNID_ERR ? remote : tun);
d20f3c9e	216	}
	217
	218	if (strcasecmp(s, "any") == 0)
a4f24bf8	219	return (SSH_TUNID_ANY);
d20f3c9e	220
a4f24bf8	221	tun = strtonum(s, 0, SSH_TUNID_MAX, &errstr);
	222	if (errstr != NULL)
	223	return (SSH_TUNID_ERR);
d20f3c9e	224
	225	return (tun);
	226	}
	227
e2b1fb42	228	#define SECONDS 1
	229	#define MINUTES (SECONDS * 60)
	230	#define HOURS (MINUTES * 60)
	231	#define DAYS (HOURS * 24)
	232	#define WEEKS (DAYS * 7)
	233
255cabd9	234	/*
	235	* Convert a time string into seconds; format is
	236	* a sequence of:
	237	* time[qualifier]
	238	*
	239	* Valid time qualifiers are:
	240	* <none> seconds
	241	* s\|S seconds
	242	* m\|M minutes
	243	* h\|H hours
	244	* d\|D days
	245	* w\|W weeks
	246	*
	247	* Examples:
	248	* 90m 90 minutes
	249	* 1h30m 90 minutes
	250	* 2d 2 days
	251	* 1w 1 week
	252	*
	253	* Return -1 if time string is invalid.
	254	*/
	255	long
	256	convtime(const char *s)
e2b1fb42	257	{
	258	long total, secs;
	259	const char *p;
	260	char *endp;
	261
	262	errno = 0;
	263	total = 0;
	264	p = s;
	265
	266	if (p == NULL \|\| *p == '\0')
	267	return -1;
	268
	269	while (*p) {
	270	secs = strtol(p, &endp, 10);
	271	if (p == endp \|\|
	272	(errno == ERANGE && (secs == LONG_MIN \|\| secs == LONG_MAX)) \|\|
	273	secs < 0)
	274	return -1;
	275
	276	switch (*endp++) {
	277	case '\0':
	278	endp--;
	279	case 's':
	280	case 'S':
	281	break;
	282	case 'm':
	283	case 'M':
	284	secs *= MINUTES;
	285	break;
	286	case 'h':
	287	case 'H':
	288	secs *= HOURS;
	289	break;
	290	case 'd':
	291	case 'D':
	292	secs *= DAYS;
	293	break;
	294	case 'w':
	295	case 'W':
	296	secs *= WEEKS;
	297	break;
	298	default:
	299	return -1;
	300	}
	301	total += secs;
	302	if (total < 0)
	303	return -1;
	304	p = endp;
	305	}
	306
	307	return total;
	308	}
	309
3867aa0a	310	/*
	311	* Search for next delimiter between hostnames/addresses and ports.
	312	* Argument may be modified (for termination).
	313	* Returns *cp if parsing succeeds.
	314	* *cp is set to the start of the next delimiter, if one was found.
	315	* If this is the last field, *cp is set to NULL.
	316	*/
	317	char *
	318	hpdelim(char **cp)
	319	{
	320	char s, old;
	321
	322	if (cp == NULL \|\| *cp == NULL)
	323	return NULL;
	324
	325	old = s = *cp;
	326	if (*s == '[') {
	327	if ((s = strchr(s, ']')) == NULL)
	328	return NULL;
	329	else
	330	s++;
	331	} else if ((s = strpbrk(s, ":/")) == NULL)
	332	s = cp + strlen(cp); /* skip to end (see first case below) */
	333
	334	switch (*s) {
	335	case '\0':
	336	cp = NULL; / no more fields*/
	337	break;
f8cc7664	338
3867aa0a	339	case ':':
	340	case '/':
	341	s = '\0'; / terminate */
	342	*cp = s + 1;
	343	break;
f8cc7664	344
3867aa0a	345	default:
	346	return NULL;
	347	}
	348
	349	return old;
	350	}
	351
1fcde3fe	352	char *
	353	cleanhostname(char *host)
	354	{
	355	if (*host == '[' && host[strlen(host) - 1] == ']') {
	356	host[strlen(host) - 1] = '\0';
	357	return (host + 1);
	358	} else
	359	return host;
	360	}
	361
	362	char *
	363	colon(char *cp)
	364	{
	365	int flag = 0;
	366
	367	if (cp == ':') / Leading colon is part of file name. */
	368	return (0);
	369	if (*cp == '[')
	370	flag = 1;
	371
	372	for (; *cp; ++cp) {
	373	if (cp == '@' && (cp+1) == '[')
	374	flag = 1;
	375	if (cp == ']' && (cp+1) == ':' && flag)
	376	return (cp+1);
	377	if (*cp == ':' && !flag)
	378	return (cp);
	379	if (*cp == '/')
	380	return (0);
	381	}
	382	return (0);
	383	}
	384
255cabd9	385	/* function to assist building execv() arguments */
8a624ebf	386	void
	387	addargs(arglist args, char fmt, ...)
	388	{
	389	va_list ap;
	390	char buf[1024];
9a995072	391	u_int nalloc;
8a624ebf	392
	393	va_start(ap, fmt);
	394	vsnprintf(buf, sizeof(buf), fmt, ap);
	395	va_end(ap);
	396
c46e584f	397	nalloc = args->nalloc;
8a624ebf	398	if (args->list == NULL) {
c46e584f	399	nalloc = 32;
8a624ebf	400	args->num = 0;
c46e584f	401	} else if (args->num+2 >= nalloc)
c46e584f	402	nalloc *= 2;
8a624ebf	403
c46e584f	404	args->list = xrealloc(args->list, nalloc * sizeof(char *));
c46e584f	405	args->nalloc = nalloc;
8a624ebf	406	args->list[args->num++] = xstrdup(buf);
	407	args->list[args->num] = NULL;
	408	}
ea067773	409
49e71137	410	/*
	411	* Expands tildes in the file name. Returns data allocated by xmalloc.
	412	* Warning: this calls getpw*.
	413	*/
	414	char *
	415	tilde_expand_filename(const char *filename, uid_t uid)
	416	{
	417	const char *path;
	418	char user[128], ret[MAXPATHLEN];
	419	struct passwd *pw;
2ceb8101	420	u_int len, slash;
49e71137	421
	422	if (*filename != '~')
	423	return (xstrdup(filename));
	424	filename++;
	425
	426	path = strchr(filename, '/');
	427	if (path != NULL && path > filename) { /* ~user/path */
2ceb8101	428	slash = path - filename;
2ceb8101	429	if (slash > sizeof(user) - 1)
49e71137	430	fatal("tilde_expand_filename: ~username too long");
2ceb8101	431	memcpy(user, filename, slash);
2ceb8101	432	user[slash] = '\0';
49e71137	433	if ((pw = getpwnam(user)) == NULL)
	434	fatal("tilde_expand_filename: No such user %s", user);
	435	} else if ((pw = getpwuid(uid)) == NULL) /* ~/path */
	436	fatal("tilde_expand_filename: No such uid %d", uid);
	437
	438	if (strlcpy(ret, pw->pw_dir, sizeof(ret)) >= sizeof(ret))
	439	fatal("tilde_expand_filename: Path too long");
	440
	441	/* Make sure directory has a trailing '/' */
	442	len = strlen(pw->pw_dir);
	443	if ((len == 0 \|\| pw->pw_dir[len - 1] != '/') &&
	444	strlcat(ret, "/", sizeof(ret)) >= sizeof(ret))
	445	fatal("tilde_expand_filename: Path too long");
	446
	447	/* Skip leading '/' from specified path */
	448	if (path != NULL)
	449	filename = path + 1;
	450	if (strlcat(ret, filename, sizeof(ret)) >= sizeof(ret))
	451	fatal("tilde_expand_filename: Path too long");
	452
	453	return (xstrdup(ret));
	454	}
	455
a980cbd7	456	/*
	457	* Expand a string with a set of %[char] escapes. A number of escapes may be
	458	* specified as (char escape_chars, char replacement) pairs. The list must
6381acf0	459	* be terminated by a NULL escape_char. Returns replaced string in memory
a980cbd7	460	* allocated by xmalloc.
	461	*/
	462	char *
	463	percent_expand(const char *string, ...)
	464	{
	465	#define EXPAND_MAX_KEYS 16
	466	struct {
	467	const char *key;
	468	const char *repl;
	469	} keys[EXPAND_MAX_KEYS];
2ceb8101	470	u_int num_keys, i, j;
a980cbd7	471	char buf[4096];
	472	va_list ap;
	473
	474	/* Gather keys */
	475	va_start(ap, string);
	476	for (num_keys = 0; num_keys < EXPAND_MAX_KEYS; num_keys++) {
	477	keys[num_keys].key = va_arg(ap, char *);
	478	if (keys[num_keys].key == NULL)
	479	break;
	480	keys[num_keys].repl = va_arg(ap, char *);
	481	if (keys[num_keys].repl == NULL)
	482	fatal("percent_expand: NULL replacement");
	483	}
	484	va_end(ap);
	485
	486	if (num_keys >= EXPAND_MAX_KEYS)
	487	fatal("percent_expand: too many keys");
	488
	489	/* Expand string */
	490	*buf = '\0';
	491	for (i = 0; *string != '\0'; string++) {
	492	if (*string != '%') {
	493	append:
	494	buf[i++] = *string;
	495	if (i >= sizeof(buf))
	496	fatal("percent_expand: string too long");
	497	buf[i] = '\0';
	498	continue;
	499	}
	500	string++;
	501	if (*string == '%')
	502	goto append;
	503	for (j = 0; j < num_keys; j++) {
	504	if (strchr(keys[j].key, *string) != NULL) {
	505	i = strlcat(buf, keys[j].repl, sizeof(buf));
	506	if (i >= sizeof(buf))
	507	fatal("percent_expand: string too long");
	508	break;
	509	}
	510	}
	511	if (j >= num_keys)
	512	fatal("percent_expand: unknown key %%%c", *string);
	513	}
	514	return (xstrdup(buf));
	515	#undef EXPAND_MAX_KEYS
	516	}
	517
ea067773	518	/*
	519	* Read an entire line from a public key file into a static buffer, discarding
	520	* lines that exceed the buffer size. Returns 0 on success, -1 on failure.
	521	*/
	522	int
	523	read_keyfile_line(FILE f, const char filename, char *buf, size_t bufsz,
41feb690	524	u_long *lineno)
ea067773	525	{
	526	while (fgets(buf, bufsz, f) != NULL) {
	527	(*lineno)++;
	528	if (buf[strlen(buf) - 1] == '\n' \|\| feof(f)) {
	529	return 0;
	530	} else {
41feb690	531	debug("%s: %s line %lu exceeds size limit", __func__,
41feb690	532	filename, *lineno);
ea067773	533	/* discard remainder of line */
f8cc7664	534	while (fgetc(f) != '\n' && !feof(f))
ea067773	535	; /* nothing */
	536	}
	537	}
	538	return -1;
	539	}
ef07103c	540
d20f3c9e	541	int
a4f24bf8	542	tun_open(int tun, int mode)
d20f3c9e	543	{
6306853a	544	#if defined(CUSTOM_SYS_TUN_OPEN)
	545	return (sys_tun_open(tun, mode));
	546	#elif defined(SSH_TUN_BSD)
a4f24bf8	547	struct ifreq ifr;
d20f3c9e	548	char name[100];
a4f24bf8	549	int fd = -1, sock;
d20f3c9e	550
a4f24bf8	551	/* Open the tunnel device */
a4f24bf8	552	if (tun <= SSH_TUNID_MAX) {
d20f3c9e	553	snprintf(name, sizeof(name), "/dev/tun%d", tun);
a4f24bf8	554	fd = open(name, O_RDWR);
	555	} else if (tun == SSH_TUNID_ANY) {
	556	for (tun = 100; tun >= 0; tun--) {
	557	snprintf(name, sizeof(name), "/dev/tun%d", tun);
	558	if ((fd = open(name, O_RDWR)) >= 0)
	559	break;
d20f3c9e	560	}
d20f3c9e	561	} else {
a4f24bf8	562	debug("%s: invalid tunnel %u\n", __func__, tun);
	563	return (-1);
	564	}
	565
	566	if (fd < 0) {
	567	debug("%s: %s open failed: %s", __func__, name, strerror(errno));
	568	return (-1);
	569	}
	570
	571	debug("%s: %s mode %d fd %d", __func__, name, mode, fd);
	572
	573	/* Set the tunnel device operation mode */
	574	snprintf(ifr.ifr_name, sizeof(ifr.ifr_name), "tun%d", tun);
	575	if ((sock = socket(PF_UNIX, SOCK_STREAM, 0)) == -1)
	576	goto failed;
	577
	578	if (ioctl(sock, SIOCGIFFLAGS, &ifr) == -1)
	579	goto failed;
	580	if (mode == SSH_TUNMODE_ETHERNET) {
	581	ifr.ifr_flags \|= IFF_LINK0;
	582	if (ioctl(sock, SIOCSIFFLAGS, &ifr) == -1)
	583	goto failed;
d20f3c9e	584	}
a4f24bf8	585	ifr.ifr_flags \|= IFF_UP;
	586	if (ioctl(sock, SIOCSIFFLAGS, &ifr) == -1)
	587	goto failed;
	588
	589	close(sock);
	590	return (fd);
	591
	592	failed:
	593	if (fd >= 0)
	594	close(fd);
	595	if (sock >= 0)
	596	close(sock);
	597	debug("%s: failed to set %s mode %d: %s", __func__, name,
	598	mode, strerror(errno));
d20f3c9e	599	return (-1);
6306853a	600	#else
	601	error("Tunnel interfaces are not supported on this platform");
	602	return (-1);
	603	#endif
d20f3c9e	604	}
d20f3c9e	605
fd6168c1	606	void
	607	sanitise_stdfd(void)
	608	{
	609	int nullfd;
	610
	611	if ((nullfd = open(_PATH_DEVNULL, O_RDWR)) == -1) {
	612	fprintf(stderr, "Couldn't open /dev/null: %s", strerror(errno));
	613	exit(1);
	614	}
	615	while (nullfd < 2) {
	616	if (dup2(nullfd, nullfd + 1) == -1) {
	617	fprintf(stderr, "dup2: %s", strerror(errno));
	618	exit(1);
	619	}
	620	nullfd++;
	621	}
	622	if (nullfd > 2)
	623	close(nullfd);
	624	}
	625
ef07103c	626	char *
	627	tohex(const u_char *d, u_int l)
	628	{
	629	char b[3], *r;
	630	u_int i, hl;
	631
	632	hl = l * 2 + 1;
	633	r = xmalloc(hl);
	634	*r = '\0';
	635	for (i = 0; i < l; i++) {
	636	snprintf(b, sizeof(b), "%02x", d[i]);
	637	strlcat(r, b, hl);
	638	}
	639	return (r);
	640	}
	641