[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 1.42 2006/01/31 10:19:02 djm Exp $");

#ifdef SSH_TUN_OPENBSD
#include <net/if.h>
#endif

#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 *cp;
	u_int nalloc;
	int r;

	va_start(ap, fmt);
	r = vasprintf(&cp, fmt, ap);
	va_end(ap);
	if (r == -1)
		fatal("addargs: argument too long");

	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++] = cp;
	args->list[args->num] = NULL;
}

void
replacearg(arglist *args, u_int which, char *fmt, ...)
{
	va_list ap;
	char *cp;
	int r;

	va_start(ap, fmt);
	r = vasprintf(&cp, fmt, ap);
	va_end(ap);
	if (r == -1)
		fatal("replacearg: argument too long");

	if (which >= args->num)
		fatal("replacearg: tried to replace invalid arg %d >= %d",
		    which, args->num);
	xfree(args->list[which]);
	args->list[which] = cp;
}

void
freeargs(arglist *args)
{
	u_int i;

	if (args->list != NULL) {
		for (i = 0; i < args->num; i++)
			xfree(args->list[i]);
		xfree(args->list);
		args->nalloc = args->num = 0;
		args->list = 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_OPENBSD)
	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", __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;

	/* Set interface mode */
	ifr.ifr_flags &= ~IFF_UP;
	if (mode == SSH_TUNMODE_ETHERNET)
		ifr.ifr_flags |= IFF_LINK0;
	else
		ifr.ifr_flags &= ~IFF_LINK0;
	if (ioctl(sock, SIOCSIFFLAGS, &ifr) == -1)
		goto failed;

	/* Bring interface up */
	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, dupfd;

	if ((nullfd = dupfd = open(_PATH_DEVNULL, O_RDWR)) == -1) {
		fprintf(stderr, "Couldn't open /dev/null: %s", strerror(errno));
		exit(1);
	}
	while (++dupfd <= 2) {
		/* Only clobber closed fds */
		if (fcntl(dupfd, F_GETFL, 0) >= 0)
			continue;
		if (dup2(nullfd, dupfd) == -1) {
			fprintf(stderr, "dup2: %s", strerror(errno));
			exit(1);
		}
	}
	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"
4116f5c0	27	RCSID("$OpenBSD: misc.c,v 1.42 2006/01/31 10:19:02 djm Exp $");
1f1fbbd8	28
	29	#ifdef SSH_TUN_OPENBSD
	30	#include <net/if.h>
	31	#endif
6d24277f	32
1aa00dcb	33	#include "misc.h"
42f11eb2	34	#include "log.h"
4ab21f86	35	#include "xmalloc.h"
6d24277f	36
255cabd9	37	/* remove newline at end of string */
6d24277f	38	char *
	39	chop(char *s)
	40	{
	41	char *t = s;
	42	while (*t) {
6aacefa7	43	if (t == '\n' \|\| t == '\r') {
6d24277f	44	*t = '\0';
	45	return s;
	46	}
	47	t++;
	48	}
	49	return s;
	50
	51	}
	52
255cabd9	53	/* set/unset filedescriptor to non-blocking */
170694d7	54	int
6d24277f	55	set_nonblock(int fd)
	56	{
	57	int val;
89aa792b	58
6d24277f	59	val = fcntl(fd, F_GETFL, 0);
	60	if (val < 0) {
	61	error("fcntl(%d, F_GETFL, 0): %s", fd, strerror(errno));
170694d7	62	return (-1);
6d24277f	63	}
a22aff1f	64	if (val & O_NONBLOCK) {
170694d7	65	debug3("fd %d is O_NONBLOCK", fd);
170694d7	66	return (0);
a22aff1f	67	}
45c42d58	68	debug2("fd %d setting O_NONBLOCK", fd);
6d24277f	69	val \|= O_NONBLOCK;
170694d7	70	if (fcntl(fd, F_SETFL, val) == -1) {
	71	debug("fcntl(%d, F_SETFL, O_NONBLOCK): %s", fd,
	72	strerror(errno));
	73	return (-1);
	74	}
	75	return (0);
6d24277f	76	}
6d24277f	77
170694d7	78	int
89aa792b	79	unset_nonblock(int fd)
	80	{
	81	int val;
	82
	83	val = fcntl(fd, F_GETFL, 0);
	84	if (val < 0) {
	85	error("fcntl(%d, F_GETFL, 0): %s", fd, strerror(errno));
170694d7	86	return (-1);
89aa792b	87	}
89aa792b	88	if (!(val & O_NONBLOCK)) {
170694d7	89	debug3("fd %d is not O_NONBLOCK", fd);
170694d7	90	return (0);
89aa792b	91	}
e04e7a19	92	debug("fd %d clearing O_NONBLOCK", fd);
89aa792b	93	val &= ~O_NONBLOCK;
170694d7	94	if (fcntl(fd, F_SETFL, val) == -1) {
170694d7	95	debug("fcntl(%d, F_SETFL, ~O_NONBLOCK): %s",
c92ec40b	96	fd, strerror(errno));
170694d7	97	return (-1);
	98	}
	99	return (0);
89aa792b	100	}
89aa792b	101
bcc0381e	102	/* disable nagle on socket */
	103	void
	104	set_nodelay(int fd)
	105	{
3c05447a	106	int opt;
3c05447a	107	socklen_t optlen;
bcc0381e	108
811a6342	109	optlen = sizeof opt;
811a6342	110	if (getsockopt(fd, IPPROTO_TCP, TCP_NODELAY, &opt, &optlen) == -1) {
f7fb35fe	111	debug("getsockopt TCP_NODELAY: %.100s", strerror(errno));
811a6342	112	return;
	113	}
	114	if (opt == 1) {
	115	debug2("fd %d is TCP_NODELAY", fd);
	116	return;
	117	}
	118	opt = 1;
6226a8f8	119	debug2("fd %d setting TCP_NODELAY", fd);
811a6342	120	if (setsockopt(fd, IPPROTO_TCP, TCP_NODELAY, &opt, sizeof opt) == -1)
bcc0381e	121	error("setsockopt TCP_NODELAY: %.100s", strerror(errno));
	122	}
	123
6d24277f	124	/* Characters considered whitespace in strsep calls. */
	125	#define WHITESPACE " \t\r\n"
	126
255cabd9	127	/* return next token in configuration line */
6d24277f	128	char *
	129	strdelim(char **s)
	130	{
	131	char *old;
	132	int wspace = 0;
	133
	134	if (*s == NULL)
	135	return NULL;
	136
	137	old = *s;
	138
	139	s = strpbrk(s, WHITESPACE "=");
	140	if (*s == NULL)
	141	return (old);
	142
	143	/* Allow only one '=' to be skipped */
	144	if (*s[0] == '=')
	145	wspace = 1;
	146	*s[0] = '\0';
	147
	148	s += strspn(s + 1, WHITESPACE) + 1;
	149	if (*s[0] == '=' && !wspace)
	150	s += strspn(s + 1, WHITESPACE) + 1;
	151
	152	return (old);
	153	}
1aa00dcb	154
3b1a83df	155	struct passwd *
	156	pwcopy(struct passwd *pw)
	157	{
	158	struct passwd copy = xmalloc(sizeof(copy));
5649fbbe	159
3b1a83df	160	memset(copy, 0, sizeof(*copy));
	161	copy->pw_name = xstrdup(pw->pw_name);
	162	copy->pw_passwd = xstrdup(pw->pw_passwd);
5649fbbe	163	copy->pw_gecos = xstrdup(pw->pw_gecos);
3b1a83df	164	copy->pw_uid = pw->pw_uid;
3b1a83df	165	copy->pw_gid = pw->pw_gid;
7751d4eb	166	#ifdef HAVE_PW_EXPIRE_IN_PASSWD
c4d49b85	167	copy->pw_expire = pw->pw_expire;
7751d4eb	168	#endif
7751d4eb	169	#ifdef HAVE_PW_CHANGE_IN_PASSWD
c4d49b85	170	copy->pw_change = pw->pw_change;
7751d4eb	171	#endif
2605addd	172	#ifdef HAVE_PW_CLASS_IN_PASSWD
3b1a83df	173	copy->pw_class = xstrdup(pw->pw_class);
2605addd	174	#endif
3b1a83df	175	copy->pw_dir = xstrdup(pw->pw_dir);
	176	copy->pw_shell = xstrdup(pw->pw_shell);
	177	return copy;
	178	}
	179
255cabd9	180	/*
	181	* Convert ASCII string to TCP/IP port number.
	182	* Port must be >0 and <=65535.
	183	* Return 0 if invalid.
	184	*/
	185	int
	186	a2port(const char *s)
2d2a2c65	187	{
	188	long port;
	189	char *endp;
	190
	191	errno = 0;
	192	port = strtol(s, &endp, 0);
	193	if (s == endp \|\| *endp != '\0' \|\|
	194	(errno == ERANGE && (port == LONG_MIN \|\| port == LONG_MAX)) \|\|
	195	port <= 0 \|\| port > 65535)
	196	return 0;
	197
	198	return port;
	199	}
	200
d20f3c9e	201	int
	202	a2tun(const char s, int remote)
	203	{
	204	const char *errstr = NULL;
	205	char sp, ep;
	206	int tun;
	207
	208	if (remote != NULL) {
a4f24bf8	209	*remote = SSH_TUNID_ANY;
d20f3c9e	210	sp = xstrdup(s);
	211	if ((ep = strchr(sp, ':')) == NULL) {
	212	xfree(sp);
	213	return (a2tun(s, NULL));
	214	}
	215	ep[0] = '\0'; ep++;
	216	*remote = a2tun(ep, NULL);
	217	tun = a2tun(sp, NULL);
	218	xfree(sp);
a4f24bf8	219	return (remote == SSH_TUNID_ERR ? remote : tun);
d20f3c9e	220	}
	221
	222	if (strcasecmp(s, "any") == 0)
a4f24bf8	223	return (SSH_TUNID_ANY);
d20f3c9e	224
a4f24bf8	225	tun = strtonum(s, 0, SSH_TUNID_MAX, &errstr);
	226	if (errstr != NULL)
	227	return (SSH_TUNID_ERR);
d20f3c9e	228
	229	return (tun);
	230	}
	231
e2b1fb42	232	#define SECONDS 1
	233	#define MINUTES (SECONDS * 60)
	234	#define HOURS (MINUTES * 60)
	235	#define DAYS (HOURS * 24)
	236	#define WEEKS (DAYS * 7)
	237
255cabd9	238	/*
	239	* Convert a time string into seconds; format is
	240	* a sequence of:
	241	* time[qualifier]
	242	*
	243	* Valid time qualifiers are:
	244	* <none> seconds
	245	* s\|S seconds
	246	* m\|M minutes
	247	* h\|H hours
	248	* d\|D days
	249	* w\|W weeks
	250	*
	251	* Examples:
	252	* 90m 90 minutes
	253	* 1h30m 90 minutes
	254	* 2d 2 days
	255	* 1w 1 week
	256	*
	257	* Return -1 if time string is invalid.
	258	*/
	259	long
	260	convtime(const char *s)
e2b1fb42	261	{
	262	long total, secs;
	263	const char *p;
	264	char *endp;
	265
	266	errno = 0;
	267	total = 0;
	268	p = s;
	269
	270	if (p == NULL \|\| *p == '\0')
	271	return -1;
	272
	273	while (*p) {
	274	secs = strtol(p, &endp, 10);
	275	if (p == endp \|\|
	276	(errno == ERANGE && (secs == LONG_MIN \|\| secs == LONG_MAX)) \|\|
	277	secs < 0)
	278	return -1;
	279
	280	switch (*endp++) {
	281	case '\0':
	282	endp--;
	283	case 's':
	284	case 'S':
	285	break;
	286	case 'm':
	287	case 'M':
	288	secs *= MINUTES;
	289	break;
	290	case 'h':
	291	case 'H':
	292	secs *= HOURS;
	293	break;
	294	case 'd':
	295	case 'D':
	296	secs *= DAYS;
	297	break;
	298	case 'w':
	299	case 'W':
	300	secs *= WEEKS;
	301	break;
	302	default:
	303	return -1;
	304	}
	305	total += secs;
	306	if (total < 0)
	307	return -1;
	308	p = endp;
	309	}
	310
	311	return total;
	312	}
	313
3867aa0a	314	/*
	315	* Search for next delimiter between hostnames/addresses and ports.
	316	* Argument may be modified (for termination).
	317	* Returns *cp if parsing succeeds.
	318	* *cp is set to the start of the next delimiter, if one was found.
	319	* If this is the last field, *cp is set to NULL.
	320	*/
	321	char *
	322	hpdelim(char **cp)
	323	{
	324	char s, old;
	325
	326	if (cp == NULL \|\| *cp == NULL)
	327	return NULL;
	328
	329	old = s = *cp;
	330	if (*s == '[') {
	331	if ((s = strchr(s, ']')) == NULL)
	332	return NULL;
	333	else
	334	s++;
	335	} else if ((s = strpbrk(s, ":/")) == NULL)
	336	s = cp + strlen(cp); /* skip to end (see first case below) */
	337
	338	switch (*s) {
	339	case '\0':
	340	cp = NULL; / no more fields*/
	341	break;
f8cc7664	342
3867aa0a	343	case ':':
	344	case '/':
	345	s = '\0'; / terminate */
	346	*cp = s + 1;
	347	break;
f8cc7664	348
3867aa0a	349	default:
	350	return NULL;
	351	}
	352
	353	return old;
	354	}
	355
1fcde3fe	356	char *
	357	cleanhostname(char *host)
	358	{
	359	if (*host == '[' && host[strlen(host) - 1] == ']') {
	360	host[strlen(host) - 1] = '\0';
	361	return (host + 1);
	362	} else
	363	return host;
	364	}
	365
	366	char *
	367	colon(char *cp)
	368	{
	369	int flag = 0;
	370
	371	if (cp == ':') / Leading colon is part of file name. */
	372	return (0);
	373	if (*cp == '[')
	374	flag = 1;
	375
	376	for (; *cp; ++cp) {
	377	if (cp == '@' && (cp+1) == '[')
	378	flag = 1;
	379	if (cp == ']' && (cp+1) == ':' && flag)
	380	return (cp+1);
	381	if (*cp == ':' && !flag)
	382	return (cp);
	383	if (*cp == '/')
	384	return (0);
	385	}
	386	return (0);
	387	}
	388
255cabd9	389	/* function to assist building execv() arguments */
8a624ebf	390	void
	391	addargs(arglist args, char fmt, ...)
	392	{
	393	va_list ap;
4116f5c0	394	char *cp;
9a995072	395	u_int nalloc;
4116f5c0	396	int r;
8a624ebf	397
8a624ebf	398	va_start(ap, fmt);
4116f5c0	399	r = vasprintf(&cp, fmt, ap);
8a624ebf	400	va_end(ap);
4116f5c0	401	if (r == -1)
4116f5c0	402	fatal("addargs: argument too long");
8a624ebf	403
c46e584f	404	nalloc = args->nalloc;
8a624ebf	405	if (args->list == NULL) {
c46e584f	406	nalloc = 32;
8a624ebf	407	args->num = 0;
c46e584f	408	} else if (args->num+2 >= nalloc)
c46e584f	409	nalloc *= 2;
8a624ebf	410
c46e584f	411	args->list = xrealloc(args->list, nalloc * sizeof(char *));
c46e584f	412	args->nalloc = nalloc;
4116f5c0	413	args->list[args->num++] = cp;
8a624ebf	414	args->list[args->num] = NULL;
8a624ebf	415	}
ea067773	416
4116f5c0	417	void
	418	replacearg(arglist args, u_int which, char fmt, ...)
	419	{
	420	va_list ap;
	421	char *cp;
	422	int r;
	423
	424	va_start(ap, fmt);
	425	r = vasprintf(&cp, fmt, ap);
	426	va_end(ap);
	427	if (r == -1)
	428	fatal("replacearg: argument too long");
	429
	430	if (which >= args->num)
	431	fatal("replacearg: tried to replace invalid arg %d >= %d",
	432	which, args->num);
	433	xfree(args->list[which]);
	434	args->list[which] = cp;
	435	}
	436
	437	void
	438	freeargs(arglist *args)
	439	{
	440	u_int i;
	441
	442	if (args->list != NULL) {
	443	for (i = 0; i < args->num; i++)
	444	xfree(args->list[i]);
	445	xfree(args->list);
	446	args->nalloc = args->num = 0;
	447	args->list = NULL;
	448	}
	449	}
	450
49e71137	451	/*
	452	* Expands tildes in the file name. Returns data allocated by xmalloc.
	453	* Warning: this calls getpw*.
	454	*/
	455	char *
	456	tilde_expand_filename(const char *filename, uid_t uid)
	457	{
	458	const char *path;
	459	char user[128], ret[MAXPATHLEN];
	460	struct passwd *pw;
2ceb8101	461	u_int len, slash;
49e71137	462
	463	if (*filename != '~')
	464	return (xstrdup(filename));
	465	filename++;
	466
	467	path = strchr(filename, '/');
	468	if (path != NULL && path > filename) { /* ~user/path */
2ceb8101	469	slash = path - filename;
2ceb8101	470	if (slash > sizeof(user) - 1)
49e71137	471	fatal("tilde_expand_filename: ~username too long");
2ceb8101	472	memcpy(user, filename, slash);
2ceb8101	473	user[slash] = '\0';
49e71137	474	if ((pw = getpwnam(user)) == NULL)
	475	fatal("tilde_expand_filename: No such user %s", user);
	476	} else if ((pw = getpwuid(uid)) == NULL) /* ~/path */
	477	fatal("tilde_expand_filename: No such uid %d", uid);
	478
	479	if (strlcpy(ret, pw->pw_dir, sizeof(ret)) >= sizeof(ret))
	480	fatal("tilde_expand_filename: Path too long");
	481
	482	/* Make sure directory has a trailing '/' */
	483	len = strlen(pw->pw_dir);
	484	if ((len == 0 \|\| pw->pw_dir[len - 1] != '/') &&
	485	strlcat(ret, "/", sizeof(ret)) >= sizeof(ret))
	486	fatal("tilde_expand_filename: Path too long");
	487
	488	/* Skip leading '/' from specified path */
	489	if (path != NULL)
	490	filename = path + 1;
	491	if (strlcat(ret, filename, sizeof(ret)) >= sizeof(ret))
	492	fatal("tilde_expand_filename: Path too long");
	493
	494	return (xstrdup(ret));
	495	}
	496
a980cbd7	497	/*
	498	* Expand a string with a set of %[char] escapes. A number of escapes may be
	499	* specified as (char escape_chars, char replacement) pairs. The list must
6381acf0	500	* be terminated by a NULL escape_char. Returns replaced string in memory
a980cbd7	501	* allocated by xmalloc.
	502	*/
	503	char *
	504	percent_expand(const char *string, ...)
	505	{
	506	#define EXPAND_MAX_KEYS 16
	507	struct {
	508	const char *key;
	509	const char *repl;
	510	} keys[EXPAND_MAX_KEYS];
2ceb8101	511	u_int num_keys, i, j;
a980cbd7	512	char buf[4096];
	513	va_list ap;
	514
	515	/* Gather keys */
	516	va_start(ap, string);
	517	for (num_keys = 0; num_keys < EXPAND_MAX_KEYS; num_keys++) {
	518	keys[num_keys].key = va_arg(ap, char *);
	519	if (keys[num_keys].key == NULL)
	520	break;
	521	keys[num_keys].repl = va_arg(ap, char *);
	522	if (keys[num_keys].repl == NULL)
	523	fatal("percent_expand: NULL replacement");
	524	}
	525	va_end(ap);
	526
	527	if (num_keys >= EXPAND_MAX_KEYS)
	528	fatal("percent_expand: too many keys");
	529
	530	/* Expand string */
	531	*buf = '\0';
	532	for (i = 0; *string != '\0'; string++) {
	533	if (*string != '%') {
	534	append:
	535	buf[i++] = *string;
	536	if (i >= sizeof(buf))
	537	fatal("percent_expand: string too long");
	538	buf[i] = '\0';
	539	continue;
	540	}
	541	string++;
	542	if (*string == '%')
	543	goto append;
	544	for (j = 0; j < num_keys; j++) {
	545	if (strchr(keys[j].key, *string) != NULL) {
	546	i = strlcat(buf, keys[j].repl, sizeof(buf));
	547	if (i >= sizeof(buf))
	548	fatal("percent_expand: string too long");
	549	break;
	550	}
	551	}
	552	if (j >= num_keys)
	553	fatal("percent_expand: unknown key %%%c", *string);
	554	}
	555	return (xstrdup(buf));
	556	#undef EXPAND_MAX_KEYS
	557	}
	558
ea067773	559	/*
	560	* Read an entire line from a public key file into a static buffer, discarding
	561	* lines that exceed the buffer size. Returns 0 on success, -1 on failure.
	562	*/
	563	int
	564	read_keyfile_line(FILE f, const char filename, char *buf, size_t bufsz,
41feb690	565	u_long *lineno)
ea067773	566	{
	567	while (fgets(buf, bufsz, f) != NULL) {
	568	(*lineno)++;
	569	if (buf[strlen(buf) - 1] == '\n' \|\| feof(f)) {
	570	return 0;
	571	} else {
41feb690	572	debug("%s: %s line %lu exceeds size limit", __func__,
41feb690	573	filename, *lineno);
ea067773	574	/* discard remainder of line */
f8cc7664	575	while (fgetc(f) != '\n' && !feof(f))
ea067773	576	; /* nothing */
	577	}
	578	}
	579	return -1;
	580	}
ef07103c	581
d20f3c9e	582	int
a4f24bf8	583	tun_open(int tun, int mode)
d20f3c9e	584	{
6306853a	585	#if defined(CUSTOM_SYS_TUN_OPEN)
6306853a	586	return (sys_tun_open(tun, mode));
0f6cb079	587	#elif defined(SSH_TUN_OPENBSD)
a4f24bf8	588	struct ifreq ifr;
d20f3c9e	589	char name[100];
a4f24bf8	590	int fd = -1, sock;
d20f3c9e	591
a4f24bf8	592	/* Open the tunnel device */
a4f24bf8	593	if (tun <= SSH_TUNID_MAX) {
d20f3c9e	594	snprintf(name, sizeof(name), "/dev/tun%d", tun);
a4f24bf8	595	fd = open(name, O_RDWR);
	596	} else if (tun == SSH_TUNID_ANY) {
	597	for (tun = 100; tun >= 0; tun--) {
	598	snprintf(name, sizeof(name), "/dev/tun%d", tun);
	599	if ((fd = open(name, O_RDWR)) >= 0)
	600	break;
d20f3c9e	601	}
d20f3c9e	602	} else {
81c042a3	603	debug("%s: invalid tunnel %u", __func__, tun);
a4f24bf8	604	return (-1);
	605	}
	606
	607	if (fd < 0) {
	608	debug("%s: %s open failed: %s", __func__, name, strerror(errno));
	609	return (-1);
	610	}
	611
	612	debug("%s: %s mode %d fd %d", __func__, name, mode, fd);
	613
	614	/* Set the tunnel device operation mode */
	615	snprintf(ifr.ifr_name, sizeof(ifr.ifr_name), "tun%d", tun);
	616	if ((sock = socket(PF_UNIX, SOCK_STREAM, 0)) == -1)
	617	goto failed;
	618
	619	if (ioctl(sock, SIOCGIFFLAGS, &ifr) == -1)
	620	goto failed;
b1b65311	621
	622	/* Set interface mode */
	623	ifr.ifr_flags &= ~IFF_UP;
	624	if (mode == SSH_TUNMODE_ETHERNET)
a4f24bf8	625	ifr.ifr_flags \|= IFF_LINK0;
b1b65311	626	else
	627	ifr.ifr_flags &= ~IFF_LINK0;
	628	if (ioctl(sock, SIOCSIFFLAGS, &ifr) == -1)
	629	goto failed;
	630
	631	/* Bring interface up */
a4f24bf8	632	ifr.ifr_flags \|= IFF_UP;
	633	if (ioctl(sock, SIOCSIFFLAGS, &ifr) == -1)
	634	goto failed;
	635
	636	close(sock);
	637	return (fd);
	638
	639	failed:
	640	if (fd >= 0)
	641	close(fd);
	642	if (sock >= 0)
	643	close(sock);
	644	debug("%s: failed to set %s mode %d: %s", __func__, name,
	645	mode, strerror(errno));
d20f3c9e	646	return (-1);
6306853a	647	#else
	648	error("Tunnel interfaces are not supported on this platform");
	649	return (-1);
	650	#endif
d20f3c9e	651	}
d20f3c9e	652
fd6168c1	653	void
	654	sanitise_stdfd(void)
	655	{
db382686	656	int nullfd, dupfd;
fd6168c1	657
db382686	658	if ((nullfd = dupfd = open(_PATH_DEVNULL, O_RDWR)) == -1) {
fd6168c1	659	fprintf(stderr, "Couldn't open /dev/null: %s", strerror(errno));
	660	exit(1);
	661	}
db382686	662	while (++dupfd <= 2) {
	663	/* Only clobber closed fds */
	664	if (fcntl(dupfd, F_GETFL, 0) >= 0)
	665	continue;
	666	if (dup2(nullfd, dupfd) == -1) {
fd6168c1	667	fprintf(stderr, "dup2: %s", strerror(errno));
	668	exit(1);
	669	}
fd6168c1	670	}
	671	if (nullfd > 2)
	672	close(nullfd);
	673	}
	674
ef07103c	675	char *
	676	tohex(const u_char *d, u_int l)
	677	{
	678	char b[3], *r;
	679	u_int i, hl;
	680
	681	hl = l * 2 + 1;
	682	r = xmalloc(hl);
	683	*r = '\0';
	684	for (i = 0; i < l; i++) {
	685	snprintf(b, sizeof(b), "%02x", d[i]);
	686	strlcat(r, b, hl);
	687	}
	688	return (r);
	689	}
	690