Adding upstream version 1:9.2p1.upstream/1%9.2p1upstream

Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>

1 files changed, 2917 insertions, 0 deletions

diff --git a/misc.c b/misc.c
new file mode 100644
index 0000000..c098dc6
--- /dev/null
+++ b/misc.c
@@ -0,0 +1,2917 @@
+/* $OpenBSD: misc.c,v 1.180 2023/01/06 02:37:04 djm Exp $ */
+/*
+ * Copyright (c) 2000 Markus Friedl.  All rights reserved.
+ * Copyright (c) 2005-2020 Damien Miller.  All rights reserved.
+ * Copyright (c) 2004 Henning Brauer <henning@openbsd.org>
+ *
+ * Permission to use, copy, modify, and distribute this software for any
+ * purpose with or without fee is hereby granted, provided that the above
+ * copyright notice and this permission notice appear in all copies.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
+ * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
+ * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
+ * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
+ * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
+ * ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
+ * OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
+ */
+
+
+#include "includes.h"
+
+#include <sys/types.h>
+#include <sys/ioctl.h>
+#include <sys/socket.h>
+#include <sys/stat.h>
+#include <sys/time.h>
+#include <sys/wait.h>
+#include <sys/un.h>
+
+#include <limits.h>
+#ifdef HAVE_LIBGEN_H
+# include <libgen.h>
+#endif
+#ifdef HAVE_POLL_H
+#include <poll.h>
+#endif
+#include <signal.h>
+#include <stdarg.h>
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+#include <time.h>
+#include <unistd.h>
+
+#include <netinet/in.h>
+#include <netinet/in_systm.h>
+#include <netinet/ip.h>
+#include <netinet/tcp.h>
+#include <arpa/inet.h>
+
+#include <ctype.h>
+#include <errno.h>
+#include <fcntl.h>
+#include <netdb.h>
+#ifdef HAVE_PATHS_H
+# include <paths.h>
+#include <pwd.h>
+#include <grp.h>
+#endif
+#ifdef SSH_TUN_OPENBSD
+#include <net/if.h>
+#endif
+
+#include "xmalloc.h"
+#include "misc.h"
+#include "log.h"
+#include "ssh.h"
+#include "sshbuf.h"
+#include "ssherr.h"
+#include "platform.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;
+
+}
+
+/* remove whitespace from end of string */
+void
+rtrim(char *s)
+{
+	size_t i;
+
+	if ((i = strlen(s)) == 0)
+		return;
+	for (i--; i > 0; i--) {
+		if (isspace((unsigned char)s[i]))
+			s[i] = '\0';
+	}
+}
+
+/* set/unset filedescriptor to non-blocking */
+int
+set_nonblock(int fd)
+{
+	int val;
+
+	val = fcntl(fd, F_GETFL);
+	if (val == -1) {
+		error("fcntl(%d, F_GETFL): %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);
+	if (val == -1) {
+		error("fcntl(%d, F_GETFL): %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);
+}
+
+const char *
+ssh_gai_strerror(int gaierr)
+{
+	if (gaierr == EAI_SYSTEM && errno != 0)
+		return strerror(errno);
+	return gai_strerror(gaierr);
+}
+
+/* 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));
+}
+
+/* Allow local port reuse in TIME_WAIT */
+int
+set_reuseaddr(int fd)
+{
+	int on = 1;
+
+	if (setsockopt(fd, SOL_SOCKET, SO_REUSEADDR, &on, sizeof(on)) == -1) {
+		error("setsockopt SO_REUSEADDR fd %d: %s", fd, strerror(errno));
+		return -1;
+	}
+	return 0;
+}
+
+/* Get/set routing domain */
+char *
+get_rdomain(int fd)
+{
+#if defined(HAVE_SYS_GET_RDOMAIN)
+	return sys_get_rdomain(fd);
+#elif defined(__OpenBSD__)
+	int rtable;
+	char *ret;
+	socklen_t len = sizeof(rtable);
+
+	if (getsockopt(fd, SOL_SOCKET, SO_RTABLE, &rtable, &len) == -1) {
+		error("Failed to get routing domain for fd %d: %s",
+		    fd, strerror(errno));
+		return NULL;
+	}
+	xasprintf(&ret, "%d", rtable);
+	return ret;
+#else /* defined(__OpenBSD__) */
+	return NULL;
+#endif
+}
+
+int
+set_rdomain(int fd, const char *name)
+{
+#if defined(HAVE_SYS_SET_RDOMAIN)
+	return sys_set_rdomain(fd, name);
+#elif defined(__OpenBSD__)
+	int rtable;
+	const char *errstr;
+
+	if (name == NULL)
+		return 0; /* default table */
+
+	rtable = (int)strtonum(name, 0, 255, &errstr);
+	if (errstr != NULL) {
+		/* Shouldn't happen */
+		error("Invalid routing domain \"%s\": %s", name, errstr);
+		return -1;
+	}
+	if (setsockopt(fd, SOL_SOCKET, SO_RTABLE,
+	    &rtable, sizeof(rtable)) == -1) {
+		error("Failed to set routing domain %d on fd %d: %s",
+		    rtable, fd, strerror(errno));
+		return -1;
+	}
+	return 0;
+#else /* defined(__OpenBSD__) */
+	error("Setting routing domain is not supported on this platform");
+	return -1;
+#endif
+}
+
+int
+get_sock_af(int fd)
+{
+	struct sockaddr_storage to;
+	socklen_t tolen = sizeof(to);
+
+	memset(&to, 0, sizeof(to));
+	if (getsockname(fd, (struct sockaddr *)&to, &tolen) == -1)
+		return -1;
+#ifdef IPV4_IN_IPV6
+	if (to.ss_family == AF_INET6 &&
+	    IN6_IS_ADDR_V4MAPPED(&((struct sockaddr_in6 *)&to)->sin6_addr))
+		return AF_INET;
+#endif
+	return to.ss_family;
+}
+
+void
+set_sock_tos(int fd, int tos)
+{
+#ifndef IP_TOS_IS_BROKEN
+	int af;
+
+	switch ((af = get_sock_af(fd))) {
+	case -1:
+		/* assume not a socket */
+		break;
+	case AF_INET:
+# ifdef IP_TOS
+		debug3_f("set socket %d IP_TOS 0x%02x", fd, tos);
+		if (setsockopt(fd, IPPROTO_IP, IP_TOS,
+		    &tos, sizeof(tos)) == -1) {
+			error("setsockopt socket %d IP_TOS %d: %s",
+			    fd, tos, strerror(errno));
+		}
+# endif /* IP_TOS */
+		break;
+	case AF_INET6:
+# ifdef IPV6_TCLASS
+		debug3_f("set socket %d IPV6_TCLASS 0x%02x", fd, tos);
+		if (setsockopt(fd, IPPROTO_IPV6, IPV6_TCLASS,
+		    &tos, sizeof(tos)) == -1) {
+			error("setsockopt socket %d IPV6_TCLASS %d: %s",
+			    fd, tos, strerror(errno));
+		}
+# endif /* IPV6_TCLASS */
+		break;
+	default:
+		debug2_f("unsupported socket family %d", af);
+		break;
+	}
+#endif /* IP_TOS_IS_BROKEN */
+}
+
+/*
+ * Wait up to *timeoutp milliseconds for events on fd. Updates
+ * *timeoutp with time remaining.
+ * Returns 0 if fd ready or -1 on timeout or error (see errno).
+ */
+static int
+waitfd(int fd, int *timeoutp, short events)
+{
+	struct pollfd pfd;
+	struct timeval t_start;
+	int oerrno, r;
+
+	pfd.fd = fd;
+	pfd.events = events;
+	for (; *timeoutp >= 0;) {
+		monotime_tv(&t_start);
+		r = poll(&pfd, 1, *timeoutp);
+		oerrno = errno;
+		ms_subtract_diff(&t_start, timeoutp);
+		errno = oerrno;
+		if (r > 0)
+			return 0;
+		else if (r == -1 && errno != EAGAIN && errno != EINTR)
+			return -1;
+		else if (r == 0)
+			break;
+	}
+	/* timeout */
+	errno = ETIMEDOUT;
+	return -1;
+}
+
+/*
+ * Wait up to *timeoutp milliseconds for fd to be readable. Updates
+ * *timeoutp with time remaining.
+ * Returns 0 if fd ready or -1 on timeout or error (see errno).
+ */
+int
+waitrfd(int fd, int *timeoutp) {
+	return waitfd(fd, timeoutp, POLLIN);
+}
+
+/*
+ * Attempt a non-blocking connect(2) to the specified address, waiting up to
+ * *timeoutp milliseconds for the connection to complete. If the timeout is
+ * <=0, then wait indefinitely.
+ *
+ * Returns 0 on success or -1 on failure.
+ */
+int
+timeout_connect(int sockfd, const struct sockaddr *serv_addr,
+    socklen_t addrlen, int *timeoutp)
+{
+	int optval = 0;
+	socklen_t optlen = sizeof(optval);
+
+	/* No timeout: just do a blocking connect() */
+	if (timeoutp == NULL || *timeoutp <= 0)
+		return connect(sockfd, serv_addr, addrlen);
+
+	set_nonblock(sockfd);
+	for (;;) {
+		if (connect(sockfd, serv_addr, addrlen) == 0) {
+			/* Succeeded already? */
+			unset_nonblock(sockfd);
+			return 0;
+		} else if (errno == EINTR)
+			continue;
+		else if (errno != EINPROGRESS)
+			return -1;
+		break;
+	}
+
+	if (waitfd(sockfd, timeoutp, POLLIN | POLLOUT) == -1)
+		return -1;
+
+	/* Completed or failed */
+	if (getsockopt(sockfd, SOL_SOCKET, SO_ERROR, &optval, &optlen) == -1) {
+		debug("getsockopt: %s", strerror(errno));
+		return -1;
+	}
+	if (optval != 0) {
+		errno = optval;
+		return -1;
+	}
+	unset_nonblock(sockfd);
+	return 0;
+}
+
+/* Characters considered whitespace in strsep calls. */
+#define WHITESPACE " \t\r\n"
+#define QUOTE	"\""
+
+/* return next token in configuration line */
+static char *
+strdelim_internal(char **s, int split_equals)
+{
+	char *old;
+	int wspace = 0;
+
+	if (*s == NULL)
+		return NULL;
+
+	old = *s;
+
+	*s = strpbrk(*s,
+	    split_equals ? WHITESPACE QUOTE "=" : WHITESPACE QUOTE);
+	if (*s == NULL)
+		return (old);
+
+	if (*s[0] == '\"') {
+		memmove(*s, *s + 1, strlen(*s)); /* move nul too */
+		/* Find matching quote */
+		if ((*s = strpbrk(*s, QUOTE)) == NULL) {
+			return (NULL);		/* no matching quote */
+		} else {
+			*s[0] = '\0';
+			*s += strspn(*s + 1, WHITESPACE) + 1;
+			return (old);
+		}
+	}
+
+	/* Allow only one '=' to be skipped */
+	if (split_equals && *s[0] == '=')
+		wspace = 1;
+	*s[0] = '\0';
+
+	/* Skip any extra whitespace after first token */
+	*s += strspn(*s + 1, WHITESPACE) + 1;
+	if (split_equals && *s[0] == '=' && !wspace)
+		*s += strspn(*s + 1, WHITESPACE) + 1;
+
+	return (old);
+}
+
+/*
+ * Return next token in configuration line; splts on whitespace or a
+ * single '=' character.
+ */
+char *
+strdelim(char **s)
+{
+	return strdelim_internal(s, 1);
+}
+
+/*
+ * Return next token in configuration line; splts on whitespace only.
+ */
+char *
+strdelimw(char **s)
+{
+	return strdelim_internal(s, 0);
+}
+
+struct passwd *
+pwcopy(struct passwd *pw)
+{
+	struct passwd *copy = xcalloc(1, sizeof(*copy));
+
+	copy->pw_name = xstrdup(pw->pw_name);
+	copy->pw_passwd = xstrdup(pw->pw_passwd == NULL ? "*" : pw->pw_passwd);
+#ifdef HAVE_STRUCT_PASSWD_PW_GECOS
+	copy->pw_gecos = xstrdup(pw->pw_gecos);
+#endif
+	copy->pw_uid = pw->pw_uid;
+	copy->pw_gid = pw->pw_gid;
+#ifdef HAVE_STRUCT_PASSWD_PW_EXPIRE
+	copy->pw_expire = pw->pw_expire;
+#endif
+#ifdef HAVE_STRUCT_PASSWD_PW_CHANGE
+	copy->pw_change = pw->pw_change;
+#endif
+#ifdef HAVE_STRUCT_PASSWD_PW_CLASS
+	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 -1 if invalid.
+ */
+int
+a2port(const char *s)
+{
+	struct servent *se;
+	long long port;
+	const char *errstr;
+
+	port = strtonum(s, 0, 65535, &errstr);
+	if (errstr == NULL)
+		return (int)port;
+	if ((se = getservbyname(s, "tcp")) != NULL)
+		return ntohs(se->s_port);
+	return -1;
+}
+
+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) {
+			free(sp);
+			return (a2tun(s, NULL));
+		}
+		ep[0] = '\0'; ep++;
+		*remote = a2tun(ep, NULL);
+		tun = a2tun(sp, NULL);
+		free(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.
+ */
+int
+convtime(const char *s)
+{
+	long total, secs, multiplier;
+	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 == INT_MIN || secs == INT_MAX)) ||
+		    secs < 0)
+			return -1;
+
+		multiplier = 1;
+		switch (*endp++) {
+		case '\0':
+			endp--;
+			break;
+		case 's':
+		case 'S':
+			break;
+		case 'm':
+		case 'M':
+			multiplier = MINUTES;
+			break;
+		case 'h':
+		case 'H':
+			multiplier = HOURS;
+			break;
+		case 'd':
+		case 'D':
+			multiplier = DAYS;
+			break;
+		case 'w':
+		case 'W':
+			multiplier = WEEKS;
+			break;
+		default:
+			return -1;
+		}
+		if (secs > INT_MAX / multiplier)
+			return -1;
+		secs *= multiplier;
+		if  (total > INT_MAX - secs)
+			return -1;
+		total += secs;
+		if (total < 0)
+			return -1;
+		p = endp;
+	}
+
+	return total;
+}
+
+#define TF_BUFS	8
+#define TF_LEN	9
+
+const char *
+fmt_timeframe(time_t t)
+{
+	char		*buf;
+	static char	 tfbuf[TF_BUFS][TF_LEN];	/* ring buffer */
+	static int	 idx = 0;
+	unsigned int	 sec, min, hrs, day;
+	unsigned long long	week;
+
+	buf = tfbuf[idx++];
+	if (idx == TF_BUFS)
+		idx = 0;
+
+	week = t;
+
+	sec = week % 60;
+	week /= 60;
+	min = week % 60;
+	week /= 60;
+	hrs = week % 24;
+	week /= 24;
+	day = week % 7;
+	week /= 7;
+
+	if (week > 0)
+		snprintf(buf, TF_LEN, "%02lluw%01ud%02uh", week, day, hrs);
+	else if (day > 0)
+		snprintf(buf, TF_LEN, "%01ud%02uh%02um", day, hrs, min);
+	else
+		snprintf(buf, TF_LEN, "%02u:%02u:%02u", hrs, min, sec);
+
+	return (buf);
+}
+
+/*
+ * Returns a standardized host+port identifier string.
+ * Caller must free returned string.
+ */
+char *
+put_host_port(const char *host, u_short port)
+{
+	char *hoststr;
+
+	if (port == 0 || port == SSH_DEFAULT_PORT)
+		return(xstrdup(host));
+	if (asprintf(&hoststr, "[%s]:%d", host, (int)port) == -1)
+		fatal("put_host_port: asprintf: %s", strerror(errno));
+	debug3("put_host_port: %s", hoststr);
+	return hoststr;
+}
+
+/*
+ * 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 field, if one was found.
+ * The delimiter char, if present, is stored in delim.
+ * If this is the last field, *cp is set to NULL.
+ */
+char *
+hpdelim2(char **cp, char *delim)
+{
+	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 '/':
+		if (delim != NULL)
+			*delim = *s;
+		*s = '\0';	/* terminate */
+		*cp = s + 1;
+		break;
+
+	default:
+		return NULL;
+	}
+
+	return old;
+}
+
+/* The common case: only accept colon as delimiter. */
+char *
+hpdelim(char **cp)
+{
+	char *r, delim = '\0';
+
+	r =  hpdelim2(cp, &delim);
+	if (delim == '/')
+		return NULL;
+	return r;
+}
+
+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 NULL;
+	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 NULL;
+	}
+	return NULL;
+}
+
+/*
+ * Parse a [user@]host:[path] string.
+ * Caller must free returned user, host and path.
+ * Any of the pointer return arguments may be NULL (useful for syntax checking).
+ * If user was not specified then *userp will be set to NULL.
+ * If host was not specified then *hostp will be set to NULL.
+ * If path was not specified then *pathp will be set to ".".
+ * Returns 0 on success, -1 on failure.
+ */
+int
+parse_user_host_path(const char *s, char **userp, char **hostp, char **pathp)
+{
+	char *user = NULL, *host = NULL, *path = NULL;
+	char *sdup, *tmp;
+	int ret = -1;
+
+	if (userp != NULL)
+		*userp = NULL;
+	if (hostp != NULL)
+		*hostp = NULL;
+	if (pathp != NULL)
+		*pathp = NULL;
+
+	sdup = xstrdup(s);
+
+	/* Check for remote syntax: [user@]host:[path] */
+	if ((tmp = colon(sdup)) == NULL)
+		goto out;
+
+	/* Extract optional path */
+	*tmp++ = '\0';
+	if (*tmp == '\0')
+		tmp = ".";
+	path = xstrdup(tmp);
+
+	/* Extract optional user and mandatory host */
+	tmp = strrchr(sdup, '@');
+	if (tmp != NULL) {
+		*tmp++ = '\0';
+		host = xstrdup(cleanhostname(tmp));
+		if (*sdup != '\0')
+			user = xstrdup(sdup);
+	} else {
+		host = xstrdup(cleanhostname(sdup));
+		user = NULL;
+	}
+
+	/* Success */
+	if (userp != NULL) {
+		*userp = user;
+		user = NULL;
+	}
+	if (hostp != NULL) {
+		*hostp = host;
+		host = NULL;
+	}
+	if (pathp != NULL) {
+		*pathp = path;
+		path = NULL;
+	}
+	ret = 0;
+out:
+	free(sdup);
+	free(user);
+	free(host);
+	free(path);
+	return ret;
+}
+
+/*
+ * Parse a [user@]host[:port] string.
+ * Caller must free returned user and host.
+ * Any of the pointer return arguments may be NULL (useful for syntax checking).
+ * If user was not specified then *userp will be set to NULL.
+ * If port was not specified then *portp will be -1.
+ * Returns 0 on success, -1 on failure.
+ */
+int
+parse_user_host_port(const char *s, char **userp, char **hostp, int *portp)
+{
+	char *sdup, *cp, *tmp;
+	char *user = NULL, *host = NULL;
+	int port = -1, ret = -1;
+
+	if (userp != NULL)
+		*userp = NULL;
+	if (hostp != NULL)
+		*hostp = NULL;
+	if (portp != NULL)
+		*portp = -1;
+
+	if ((sdup = tmp = strdup(s)) == NULL)
+		return -1;
+	/* Extract optional username */
+	if ((cp = strrchr(tmp, '@')) != NULL) {
+		*cp = '\0';
+		if (*tmp == '\0')
+			goto out;
+		if ((user = strdup(tmp)) == NULL)
+			goto out;
+		tmp = cp + 1;
+	}
+	/* Extract mandatory hostname */
+	if ((cp = hpdelim(&tmp)) == NULL || *cp == '\0')
+		goto out;
+	host = xstrdup(cleanhostname(cp));
+	/* Convert and verify optional port */
+	if (tmp != NULL && *tmp != '\0') {
+		if ((port = a2port(tmp)) <= 0)
+			goto out;
+	}
+	/* Success */
+	if (userp != NULL) {
+		*userp = user;
+		user = NULL;
+	}
+	if (hostp != NULL) {
+		*hostp = host;
+		host = NULL;
+	}
+	if (portp != NULL)
+		*portp = port;
+	ret = 0;
+ out:
+	free(sdup);
+	free(user);
+	free(host);
+	return ret;
+}
+
+/*
+ * Converts a two-byte hex string to decimal.
+ * Returns the decimal value or -1 for invalid input.
+ */
+static int
+hexchar(const char *s)
+{
+	unsigned char result[2];
+	int i;
+
+	for (i = 0; i < 2; i++) {
+		if (s[i] >= '0' && s[i] <= '9')
+			result[i] = (unsigned char)(s[i] - '0');
+		else if (s[i] >= 'a' && s[i] <= 'f')
+			result[i] = (unsigned char)(s[i] - 'a') + 10;
+		else if (s[i] >= 'A' && s[i] <= 'F')
+			result[i] = (unsigned char)(s[i] - 'A') + 10;
+		else
+			return -1;
+	}
+	return (result[0] << 4) | result[1];
+}
+
+/*
+ * Decode an url-encoded string.
+ * Returns a newly allocated string on success or NULL on failure.
+ */
+static char *
+urldecode(const char *src)
+{
+	char *ret, *dst;
+	int ch;
+
+	ret = xmalloc(strlen(src) + 1);
+	for (dst = ret; *src != '\0'; src++) {
+		switch (*src) {
+		case '+':
+			*dst++ = ' ';
+			break;
+		case '%':
+			if (!isxdigit((unsigned char)src[1]) ||
+			    !isxdigit((unsigned char)src[2]) ||
+			    (ch = hexchar(src + 1)) == -1) {
+				free(ret);
+				return NULL;
+			}
+			*dst++ = ch;
+			src += 2;
+			break;
+		default:
+			*dst++ = *src;
+			break;
+		}
+	}
+	*dst = '\0';
+
+	return ret;
+}
+
+/*
+ * Parse an (scp|ssh|sftp)://[user@]host[:port][/path] URI.
+ * See https://tools.ietf.org/html/draft-ietf-secsh-scp-sftp-ssh-uri-04
+ * Either user or path may be url-encoded (but not host or port).
+ * Caller must free returned user, host and path.
+ * Any of the pointer return arguments may be NULL (useful for syntax checking)
+ * but the scheme must always be specified.
+ * If user was not specified then *userp will be set to NULL.
+ * If port was not specified then *portp will be -1.
+ * If path was not specified then *pathp will be set to NULL.
+ * Returns 0 on success, 1 if non-uri/wrong scheme, -1 on error/invalid uri.
+ */
+int
+parse_uri(const char *scheme, const char *uri, char **userp, char **hostp,
+    int *portp, char **pathp)
+{
+	char *uridup, *cp, *tmp, ch;
+	char *user = NULL, *host = NULL, *path = NULL;
+	int port = -1, ret = -1;
+	size_t len;
+
+	len = strlen(scheme);
+	if (strncmp(uri, scheme, len) != 0 || strncmp(uri + len, "://", 3) != 0)
+		return 1;
+	uri += len + 3;
+
+	if (userp != NULL)
+		*userp = NULL;
+	if (hostp != NULL)
+		*hostp = NULL;
+	if (portp != NULL)
+		*portp = -1;
+	if (pathp != NULL)
+		*pathp = NULL;
+
+	uridup = tmp = xstrdup(uri);
+
+	/* Extract optional ssh-info (username + connection params) */
+	if ((cp = strchr(tmp, '@')) != NULL) {
+		char *delim;
+
+		*cp = '\0';
+		/* Extract username and connection params */
+		if ((delim = strchr(tmp, ';')) != NULL) {
+			/* Just ignore connection params for now */
+			*delim = '\0';
+		}
+		if (*tmp == '\0') {
+			/* Empty username */
+			goto out;
+		}
+		if ((user = urldecode(tmp)) == NULL)
+			goto out;
+		tmp = cp + 1;
+	}
+
+	/* Extract mandatory hostname */
+	if ((cp = hpdelim2(&tmp, &ch)) == NULL || *cp == '\0')
+		goto out;
+	host = xstrdup(cleanhostname(cp));
+	if (!valid_domain(host, 0, NULL))
+		goto out;
+
+	if (tmp != NULL && *tmp != '\0') {
+		if (ch == ':') {
+			/* Convert and verify port. */
+			if ((cp = strchr(tmp, '/')) != NULL)
+				*cp = '\0';
+			if ((port = a2port(tmp)) <= 0)
+				goto out;
+			tmp = cp ? cp + 1 : NULL;
+		}
+		if (tmp != NULL && *tmp != '\0') {
+			/* Extract optional path */
+			if ((path = urldecode(tmp)) == NULL)
+				goto out;
+		}
+	}
+
+	/* Success */
+	if (userp != NULL) {
+		*userp = user;
+		user = NULL;
+	}
+	if (hostp != NULL) {
+		*hostp = host;
+		host = NULL;
+	}
+	if (portp != NULL)
+		*portp = port;
+	if (pathp != NULL) {
+		*pathp = path;
+		path = NULL;
+	}
+	ret = 0;
+ out:
+	free(uridup);
+	free(user);
+	free(host);
+	free(path);
+	return ret;
+}
+
+/* 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_f("argument too long");
+
+	nalloc = args->nalloc;
+	if (args->list == NULL) {
+		nalloc = 32;
+		args->num = 0;
+	} else if (args->num > (256 * 1024))
+		fatal_f("too many arguments");
+	else if (args->num >= args->nalloc)
+		fatal_f("arglist corrupt");
+	else if (args->num+2 >= nalloc)
+		nalloc *= 2;
+
+	args->list = xrecallocarray(args->list, args->nalloc,
+	    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_f("argument too long");
+	if (args->list == NULL || args->num >= args->nalloc)
+		fatal_f("arglist corrupt");
+
+	if (which >= args->num)
+		fatal_f("tried to replace invalid arg %d >= %d",
+		    which, args->num);
+	free(args->list[which]);
+	args->list[which] = cp;
+}
+
+void
+freeargs(arglist *args)
+{
+	u_int i;
+
+	if (args == NULL)
+		return;
+	if (args->list != NULL && args->num < args->nalloc) {
+		for (i = 0; i < args->num; i++)
+			free(args->list[i]);
+		free(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*.
+ */
+int
+tilde_expand(const char *filename, uid_t uid, char **retp)
+{
+	char *ocopy = NULL, *copy, *s = NULL;
+	const char *path = NULL, *user = NULL;
+	struct passwd *pw;
+	size_t len;
+	int ret = -1, r, slash;
+
+	*retp = NULL;
+	if (*filename != '~') {
+		*retp = xstrdup(filename);
+		return 0;
+	}
+	ocopy = copy = xstrdup(filename + 1);
+
+	if (*copy == '\0')				/* ~ */
+		path = NULL;
+	else if (*copy == '/') {
+		copy += strspn(copy, "/");
+		if (*copy == '\0')
+			path = NULL;			/* ~/ */
+		else
+			path = copy;			/* ~/path */
+	} else {
+		user = copy;
+		if ((path = strchr(copy, '/')) != NULL) {
+			copy[path - copy] = '\0';
+			path++;
+			path += strspn(path, "/");
+			if (*path == '\0')		/* ~user/ */
+				path = NULL;
+			/* else				 ~user/path */
+		}
+		/* else					~user */
+	}
+	if (user != NULL) {
+		if ((pw = getpwnam(user)) == NULL) {
+			error_f("No such user %s", user);
+			goto out;
+		}
+	} else if ((pw = getpwuid(uid)) == NULL) {
+		error_f("No such uid %ld", (long)uid);
+		goto out;
+	}
+
+	/* Make sure directory has a trailing '/' */
+	slash = (len = strlen(pw->pw_dir)) == 0 || pw->pw_dir[len - 1] != '/';
+
+	if ((r = xasprintf(&s, "%s%s%s", pw->pw_dir,
+	    slash ? "/" : "", path != NULL ? path : "")) <= 0) {
+		error_f("xasprintf failed");
+		goto out;
+	}
+	if (r >= PATH_MAX) {
+		error_f("Path too long");
+		goto out;
+	}
+	/* success */
+	ret = 0;
+	*retp = s;
+	s = NULL;
+ out:
+	free(s);
+	free(ocopy);
+	return ret;
+}
+
+char *
+tilde_expand_filename(const char *filename, uid_t uid)
+{
+	char *ret;
+
+	if (tilde_expand(filename, uid, &ret) != 0)
+		cleanup_exit(255);
+	return ret;
+}
+
+/*
+ * Expand a string with a set of %[char] escapes and/or ${ENVIRONMENT}
+ * substitutions.  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 which the caller must free.
+ */
+static char *
+vdollar_percent_expand(int *parseerror, int dollar, int percent,
+    const char *string, va_list ap)
+{
+#define EXPAND_MAX_KEYS	16
+	u_int num_keys = 0, i;
+	struct {
+		const char *key;
+		const char *repl;
+	} keys[EXPAND_MAX_KEYS];
+	struct sshbuf *buf;
+	int r, missingvar = 0;
+	char *ret = NULL, *var, *varend, *val;
+	size_t len;
+
+	if ((buf = sshbuf_new()) == NULL)
+		fatal_f("sshbuf_new failed");
+	if (parseerror == NULL)
+		fatal_f("null parseerror arg");
+	*parseerror = 1;
+
+	/* Gather keys if we're doing percent expansion. */
+	if (percent) {
+		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_f("NULL replacement for token %s",
+				    keys[num_keys].key);
+			}
+		}
+		if (num_keys == EXPAND_MAX_KEYS && va_arg(ap, char *) != NULL)
+			fatal_f("too many keys");
+		if (num_keys == 0)
+			fatal_f("percent expansion without token list");
+	}
+
+	/* Expand string */
+	for (i = 0; *string != '\0'; string++) {
+		/* Optionally process ${ENVIRONMENT} expansions. */
+		if (dollar && string[0] == '$' && string[1] == '{') {
+			string += 2;  /* skip over '${' */
+			if ((varend = strchr(string, '}')) == NULL) {
+				error_f("environment variable '%s' missing "
+				    "closing '}'", string);
+				goto out;
+			}
+			len = varend - string;
+			if (len == 0) {
+				error_f("zero-length environment variable");
+				goto out;
+			}
+			var = xmalloc(len + 1);
+			(void)strlcpy(var, string, len + 1);
+			if ((val = getenv(var)) == NULL) {
+				error_f("env var ${%s} has no value", var);
+				missingvar = 1;
+			} else {
+				debug3_f("expand ${%s} -> '%s'", var, val);
+				if ((r = sshbuf_put(buf, val, strlen(val))) !=0)
+					fatal_fr(r, "sshbuf_put ${}");
+			}
+			free(var);
+			string += len;
+			continue;
+		}
+
+		/*
+		 * Process percent expansions if we have a list of TOKENs.
+		 * If we're not doing percent expansion everything just gets
+		 * appended here.
+		 */
+		if (*string != '%' || !percent) {
+ append:
+			if ((r = sshbuf_put_u8(buf, *string)) != 0)
+				fatal_fr(r, "sshbuf_put_u8 %%");
+			continue;
+		}
+		string++;
+		/* %% case */
+		if (*string == '%')
+			goto append;
+		if (*string == '\0') {
+			error_f("invalid format");
+			goto out;
+		}
+		for (i = 0; i < num_keys; i++) {
+			if (strchr(keys[i].key, *string) != NULL) {
+				if ((r = sshbuf_put(buf, keys[i].repl,
+				    strlen(keys[i].repl))) != 0)
+					fatal_fr(r, "sshbuf_put %%-repl");
+				break;
+			}
+		}
+		if (i >= num_keys) {
+			error_f("unknown key %%%c", *string);
+			goto out;
+		}
+	}
+	if (!missingvar && (ret = sshbuf_dup_string(buf)) == NULL)
+		fatal_f("sshbuf_dup_string failed");
+	*parseerror = 0;
+ out:
+	sshbuf_free(buf);
+	return *parseerror ? NULL : ret;
+#undef EXPAND_MAX_KEYS
+}
+
+/*
+ * Expand only environment variables.
+ * Note that although this function is variadic like the other similar
+ * functions, any such arguments will be unused.
+ */
+
+char *
+dollar_expand(int *parseerr, const char *string, ...)
+{
+	char *ret;
+	int err;
+	va_list ap;
+
+	va_start(ap, string);
+	ret = vdollar_percent_expand(&err, 1, 0, string, ap);
+	va_end(ap);
+	if (parseerr != NULL)
+		*parseerr = err;
+	return ret;
+}
+
+/*
+ * Returns expanded string or NULL if a specified environment variable is
+ * not defined, or calls fatal if the string is invalid.
+ */
+char *
+percent_expand(const char *string, ...)
+{
+	char *ret;
+	int err;
+	va_list ap;
+
+	va_start(ap, string);
+	ret = vdollar_percent_expand(&err, 0, 1, string, ap);
+	va_end(ap);
+	if (err)
+		fatal_f("failed");
+	return ret;
+}
+
+/*
+ * Returns expanded string or NULL if a specified environment variable is
+ * not defined, or calls fatal if the string is invalid.
+ */
+char *
+percent_dollar_expand(const char *string, ...)
+{
+	char *ret;
+	int err;
+	va_list ap;
+
+	va_start(ap, string);
+	ret = vdollar_percent_expand(&err, 1, 1, string, ap);
+	va_end(ap);
+	if (err)
+		fatal_f("failed");
+	return ret;
+}
+
+int
+tun_open(int tun, int mode, char **ifname)
+{
+#if defined(CUSTOM_SYS_TUN_OPEN)
+	return (sys_tun_open(tun, mode, ifname));
+#elif defined(SSH_TUN_OPENBSD)
+	struct ifreq ifr;
+	char name[100];
+	int fd = -1, sock;
+	const char *tunbase = "tun";
+
+	if (ifname != NULL)
+		*ifname = NULL;
+
+	if (mode == SSH_TUNMODE_ETHERNET)
+		tunbase = "tap";
+
+	/* Open the tunnel device */
+	if (tun <= SSH_TUNID_MAX) {
+		snprintf(name, sizeof(name), "/dev/%s%d", tunbase, tun);
+		fd = open(name, O_RDWR);
+	} else if (tun == SSH_TUNID_ANY) {
+		for (tun = 100; tun >= 0; tun--) {
+			snprintf(name, sizeof(name), "/dev/%s%d",
+			    tunbase, tun);
+			if ((fd = open(name, O_RDWR)) >= 0)
+				break;
+		}
+	} else {
+		debug_f("invalid tunnel %u", tun);
+		return -1;
+	}
+
+	if (fd == -1) {
+		debug_f("%s open: %s", name, strerror(errno));
+		return -1;
+	}
+
+	debug_f("%s mode %d fd %d", name, mode, fd);
+
+	/* Bring interface up if it is not already */
+	snprintf(ifr.ifr_name, sizeof(ifr.ifr_name), "%s%d", tunbase, tun);
+	if ((sock = socket(PF_UNIX, SOCK_STREAM, 0)) == -1)
+		goto failed;
+
+	if (ioctl(sock, SIOCGIFFLAGS, &ifr) == -1) {
+		debug_f("get interface %s flags: %s", ifr.ifr_name,
+		    strerror(errno));
+		goto failed;
+	}
+
+	if (!(ifr.ifr_flags & IFF_UP)) {
+		ifr.ifr_flags |= IFF_UP;
+		if (ioctl(sock, SIOCSIFFLAGS, &ifr) == -1) {
+			debug_f("activate interface %s: %s", ifr.ifr_name,
+			    strerror(errno));
+			goto failed;
+		}
+	}
+
+	if (ifname != NULL)
+		*ifname = xstrdup(ifr.ifr_name);
+
+	close(sock);
+	return fd;
+
+ failed:
+	if (fd >= 0)
+		close(fd);
+	if (sock >= 0)
+		close(sock);
+	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\n",
+		    strerror(errno));
+		exit(1);
+	}
+	while (++dupfd <= STDERR_FILENO) {
+		/* Only populate closed fds. */
+		if (fcntl(dupfd, F_GETFL) == -1 && errno == EBADF) {
+			if (dup2(nullfd, dupfd) == -1) {
+				fprintf(stderr, "dup2: %s\n", strerror(errno));
+				exit(1);
+			}
+		}
+	}
+	if (nullfd > STDERR_FILENO)
+		close(nullfd);
+}
+
+char *
+tohex(const void *vp, size_t l)
+{
+	const u_char *p = (const u_char *)vp;
+	char b[3], *r;
+	size_t i, hl;
+
+	if (l > 65536)
+		return xstrdup("tohex: length > 65536");
+
+	hl = l * 2 + 1;
+	r = xcalloc(1, hl);
+	for (i = 0; i < l; i++) {
+		snprintf(b, sizeof(b), "%02x", p[i]);
+		strlcat(r, b, hl);
+	}
+	return (r);
+}
+
+/*
+ * Extend string *sp by the specified format. If *sp is not NULL (or empty),
+ * then the separator 'sep' will be prepended before the formatted arguments.
+ * Extended strings are heap allocated.
+ */
+void
+xextendf(char **sp, const char *sep, const char *fmt, ...)
+{
+	va_list ap;
+	char *tmp1, *tmp2;
+
+	va_start(ap, fmt);
+	xvasprintf(&tmp1, fmt, ap);
+	va_end(ap);
+
+	if (*sp == NULL || **sp == '\0') {
+		free(*sp);
+		*sp = tmp1;
+		return;
+	}
+	xasprintf(&tmp2, "%s%s%s", *sp, sep == NULL ? "" : sep, tmp1);
+	free(tmp1);
+	free(*sp);
+	*sp = tmp2;
+}
+
+
+u_int64_t
+get_u64(const void *vp)
+{
+	const u_char *p = (const u_char *)vp;
+	u_int64_t v;
+
+	v  = (u_int64_t)p[0] << 56;
+	v |= (u_int64_t)p[1] << 48;
+	v |= (u_int64_t)p[2] << 40;
+	v |= (u_int64_t)p[3] << 32;
+	v |= (u_int64_t)p[4] << 24;
+	v |= (u_int64_t)p[5] << 16;
+	v |= (u_int64_t)p[6] << 8;
+	v |= (u_int64_t)p[7];
+
+	return (v);
+}
+
+u_int32_t
+get_u32(const void *vp)
+{
+	const u_char *p = (const u_char *)vp;
+	u_int32_t v;
+
+	v  = (u_int32_t)p[0] << 24;
+	v |= (u_int32_t)p[1] << 16;
+	v |= (u_int32_t)p[2] << 8;
+	v |= (u_int32_t)p[3];
+
+	return (v);
+}
+
+u_int32_t
+get_u32_le(const void *vp)
+{
+	const u_char *p = (const u_char *)vp;
+	u_int32_t v;
+
+	v  = (u_int32_t)p[0];
+	v |= (u_int32_t)p[1] << 8;
+	v |= (u_int32_t)p[2] << 16;
+	v |= (u_int32_t)p[3] << 24;
+
+	return (v);
+}
+
+u_int16_t
+get_u16(const void *vp)
+{
+	const u_char *p = (const u_char *)vp;
+	u_int16_t v;
+
+	v  = (u_int16_t)p[0] << 8;
+	v |= (u_int16_t)p[1];
+
+	return (v);
+}
+
+void
+put_u64(void *vp, u_int64_t v)
+{
+	u_char *p = (u_char *)vp;
+
+	p[0] = (u_char)(v >> 56) & 0xff;
+	p[1] = (u_char)(v >> 48) & 0xff;
+	p[2] = (u_char)(v >> 40) & 0xff;
+	p[3] = (u_char)(v >> 32) & 0xff;
+	p[4] = (u_char)(v >> 24) & 0xff;
+	p[5] = (u_char)(v >> 16) & 0xff;
+	p[6] = (u_char)(v >> 8) & 0xff;
+	p[7] = (u_char)v & 0xff;
+}
+
+void
+put_u32(void *vp, u_int32_t v)
+{
+	u_char *p = (u_char *)vp;
+
+	p[0] = (u_char)(v >> 24) & 0xff;
+	p[1] = (u_char)(v >> 16) & 0xff;
+	p[2] = (u_char)(v >> 8) & 0xff;
+	p[3] = (u_char)v & 0xff;
+}
+
+void
+put_u32_le(void *vp, u_int32_t v)
+{
+	u_char *p = (u_char *)vp;
+
+	p[0] = (u_char)v & 0xff;
+	p[1] = (u_char)(v >> 8) & 0xff;
+	p[2] = (u_char)(v >> 16) & 0xff;
+	p[3] = (u_char)(v >> 24) & 0xff;
+}
+
+void
+put_u16(void *vp, u_int16_t v)
+{
+	u_char *p = (u_char *)vp;
+
+	p[0] = (u_char)(v >> 8) & 0xff;
+	p[1] = (u_char)v & 0xff;
+}
+
+void
+ms_subtract_diff(struct timeval *start, int *ms)
+{
+	struct timeval diff, finish;
+
+	monotime_tv(&finish);
+	timersub(&finish, start, &diff);
+	*ms -= (diff.tv_sec * 1000) + (diff.tv_usec / 1000);
+}
+
+void
+ms_to_timespec(struct timespec *ts, int ms)
+{
+	if (ms < 0)
+		ms = 0;
+	ts->tv_sec = ms / 1000;
+	ts->tv_nsec = (ms % 1000) * 1000 * 1000;
+}
+
+void
+monotime_ts(struct timespec *ts)
+{
+	struct timeval tv;
+#if defined(HAVE_CLOCK_GETTIME) && (defined(CLOCK_BOOTTIME) || \
+    defined(CLOCK_MONOTONIC) || defined(CLOCK_REALTIME))
+	static int gettime_failed = 0;
+
+	if (!gettime_failed) {
+# ifdef CLOCK_BOOTTIME
+		if (clock_gettime(CLOCK_BOOTTIME, ts) == 0)
+			return;
+# endif /* CLOCK_BOOTTIME */
+# ifdef CLOCK_MONOTONIC
+		if (clock_gettime(CLOCK_MONOTONIC, ts) == 0)
+			return;
+# endif /* CLOCK_MONOTONIC */
+# ifdef CLOCK_REALTIME
+		/* Not monotonic, but we're almost out of options here. */
+		if (clock_gettime(CLOCK_REALTIME, ts) == 0)
+			return;
+# endif /* CLOCK_REALTIME */
+		debug3("clock_gettime: %s", strerror(errno));
+		gettime_failed = 1;
+	}
+#endif /* HAVE_CLOCK_GETTIME && (BOOTTIME || MONOTONIC || REALTIME) */
+	gettimeofday(&tv, NULL);
+	ts->tv_sec = tv.tv_sec;
+	ts->tv_nsec = (long)tv.tv_usec * 1000;
+}
+
+void
+monotime_tv(struct timeval *tv)
+{
+	struct timespec ts;
+
+	monotime_ts(&ts);
+	tv->tv_sec = ts.tv_sec;
+	tv->tv_usec = ts.tv_nsec / 1000;
+}
+
+time_t
+monotime(void)
+{
+	struct timespec ts;
+
+	monotime_ts(&ts);
+	return ts.tv_sec;
+}
+
+double
+monotime_double(void)
+{
+	struct timespec ts;
+
+	monotime_ts(&ts);
+	return ts.tv_sec + ((double)ts.tv_nsec / 1000000000);
+}
+
+void
+bandwidth_limit_init(struct bwlimit *bw, u_int64_t kbps, size_t buflen)
+{
+	bw->buflen = buflen;
+	bw->rate = kbps;
+	bw->thresh = buflen;
+	bw->lamt = 0;
+	timerclear(&bw->bwstart);
+	timerclear(&bw->bwend);
+}
+
+/* Callback from read/write loop to insert bandwidth-limiting delays */
+void
+bandwidth_limit(struct bwlimit *bw, size_t read_len)
+{
+	u_int64_t waitlen;
+	struct timespec ts, rm;
+
+	bw->lamt += read_len;
+	if (!timerisset(&bw->bwstart)) {
+		monotime_tv(&bw->bwstart);
+		return;
+	}
+	if (bw->lamt < bw->thresh)
+		return;
+
+	monotime_tv(&bw->bwend);
+	timersub(&bw->bwend, &bw->bwstart, &bw->bwend);
+	if (!timerisset(&bw->bwend))
+		return;
+
+	bw->lamt *= 8;
+	waitlen = (double)1000000L * bw->lamt / bw->rate;
+
+	bw->bwstart.tv_sec = waitlen / 1000000L;
+	bw->bwstart.tv_usec = waitlen % 1000000L;
+
+	if (timercmp(&bw->bwstart, &bw->bwend, >)) {
+		timersub(&bw->bwstart, &bw->bwend, &bw->bwend);
+
+		/* Adjust the wait time */
+		if (bw->bwend.tv_sec) {
+			bw->thresh /= 2;
+			if (bw->thresh < bw->buflen / 4)
+				bw->thresh = bw->buflen / 4;
+		} else if (bw->bwend.tv_usec < 10000) {
+			bw->thresh *= 2;
+			if (bw->thresh > bw->buflen * 8)
+				bw->thresh = bw->buflen * 8;
+		}
+
+		TIMEVAL_TO_TIMESPEC(&bw->bwend, &ts);
+		while (nanosleep(&ts, &rm) == -1) {
+			if (errno != EINTR)
+				break;
+			ts = rm;
+		}
+	}
+
+	bw->lamt = 0;
+	monotime_tv(&bw->bwstart);
+}
+
+/* Make a template filename for mk[sd]temp() */
+void
+mktemp_proto(char *s, size_t len)
+{
+	const char *tmpdir;
+	int r;
+
+	if ((tmpdir = getenv("TMPDIR")) != NULL) {
+		r = snprintf(s, len, "%s/ssh-XXXXXXXXXXXX", tmpdir);
+		if (r > 0 && (size_t)r < len)
+			return;
+	}
+	r = snprintf(s, len, "/tmp/ssh-XXXXXXXXXXXX");
+	if (r < 0 || (size_t)r >= len)
+		fatal_f("template string too short");
+}
+
+static const struct {
+	const char *name;
+	int value;
+} ipqos[] = {
+	{ "none", INT_MAX },		/* can't use 0 here; that's CS0 */
+	{ "af11", IPTOS_DSCP_AF11 },
+	{ "af12", IPTOS_DSCP_AF12 },
+	{ "af13", IPTOS_DSCP_AF13 },
+	{ "af21", IPTOS_DSCP_AF21 },
+	{ "af22", IPTOS_DSCP_AF22 },
+	{ "af23", IPTOS_DSCP_AF23 },
+	{ "af31", IPTOS_DSCP_AF31 },
+	{ "af32", IPTOS_DSCP_AF32 },
+	{ "af33", IPTOS_DSCP_AF33 },
+	{ "af41", IPTOS_DSCP_AF41 },
+	{ "af42", IPTOS_DSCP_AF42 },
+	{ "af43", IPTOS_DSCP_AF43 },
+	{ "cs0", IPTOS_DSCP_CS0 },
+	{ "cs1", IPTOS_DSCP_CS1 },
+	{ "cs2", IPTOS_DSCP_CS2 },
+	{ "cs3", IPTOS_DSCP_CS3 },
+	{ "cs4", IPTOS_DSCP_CS4 },
+	{ "cs5", IPTOS_DSCP_CS5 },
+	{ "cs6", IPTOS_DSCP_CS6 },
+	{ "cs7", IPTOS_DSCP_CS7 },
+	{ "ef", IPTOS_DSCP_EF },
+	{ "le", IPTOS_DSCP_LE },
+	{ "lowdelay", IPTOS_LOWDELAY },
+	{ "throughput", IPTOS_THROUGHPUT },
+	{ "reliability", IPTOS_RELIABILITY },
+	{ NULL, -1 }
+};
+
+int
+parse_ipqos(const char *cp)
+{
+	u_int i;
+	char *ep;
+	long val;
+
+	if (cp == NULL)
+		return -1;
+	for (i = 0; ipqos[i].name != NULL; i++) {
+		if (strcasecmp(cp, ipqos[i].name) == 0)
+			return ipqos[i].value;
+	}
+	/* Try parsing as an integer */
+	val = strtol(cp, &ep, 0);
+	if (*cp == '\0' || *ep != '\0' || val < 0 || val > 255)
+		return -1;
+	return val;
+}
+
+const char *
+iptos2str(int iptos)
+{
+	int i;
+	static char iptos_str[sizeof "0xff"];
+
+	for (i = 0; ipqos[i].name != NULL; i++) {
+		if (ipqos[i].value == iptos)
+			return ipqos[i].name;
+	}
+	snprintf(iptos_str, sizeof iptos_str, "0x%02x", iptos);
+	return iptos_str;
+}
+
+void
+lowercase(char *s)
+{
+	for (; *s; s++)
+		*s = tolower((u_char)*s);
+}
+
+int
+unix_listener(const char *path, int backlog, int unlink_first)
+{
+	struct sockaddr_un sunaddr;
+	int saved_errno, sock;
+
+	memset(&sunaddr, 0, sizeof(sunaddr));
+	sunaddr.sun_family = AF_UNIX;
+	if (strlcpy(sunaddr.sun_path, path,
+	    sizeof(sunaddr.sun_path)) >= sizeof(sunaddr.sun_path)) {
+		error_f("path \"%s\" too long for Unix domain socket", path);
+		errno = ENAMETOOLONG;
+		return -1;
+	}
+
+	sock = socket(PF_UNIX, SOCK_STREAM, 0);
+	if (sock == -1) {
+		saved_errno = errno;
+		error_f("socket: %.100s", strerror(errno));
+		errno = saved_errno;
+		return -1;
+	}
+	if (unlink_first == 1) {
+		if (unlink(path) != 0 && errno != ENOENT)
+			error("unlink(%s): %.100s", path, strerror(errno));
+	}
+	if (bind(sock, (struct sockaddr *)&sunaddr, sizeof(sunaddr)) == -1) {
+		saved_errno = errno;
+		error_f("cannot bind to path %s: %s", path, strerror(errno));
+		close(sock);
+		errno = saved_errno;
+		return -1;
+	}
+	if (listen(sock, backlog) == -1) {
+		saved_errno = errno;
+		error_f("cannot listen on path %s: %s", path, strerror(errno));
+		close(sock);
+		unlink(path);
+		errno = saved_errno;
+		return -1;
+	}
+	return sock;
+}
+
+void
+sock_set_v6only(int s)
+{
+#if defined(IPV6_V6ONLY) && !defined(__OpenBSD__)
+	int on = 1;
+
+	debug3("%s: set socket %d IPV6_V6ONLY", __func__, s);
+	if (setsockopt(s, IPPROTO_IPV6, IPV6_V6ONLY, &on, sizeof(on)) == -1)
+		error("setsockopt IPV6_V6ONLY: %s", strerror(errno));
+#endif
+}
+
+/*
+ * Compares two strings that maybe be NULL. Returns non-zero if strings
+ * are both NULL or are identical, returns zero otherwise.
+ */
+static int
+strcmp_maybe_null(const char *a, const char *b)
+{
+	if ((a == NULL && b != NULL) || (a != NULL && b == NULL))
+		return 0;
+	if (a != NULL && strcmp(a, b) != 0)
+		return 0;
+	return 1;
+}
+
+/*
+ * Compare two forwards, returning non-zero if they are identical or
+ * zero otherwise.
+ */
+int
+forward_equals(const struct Forward *a, const struct Forward *b)
+{
+	if (strcmp_maybe_null(a->listen_host, b->listen_host) == 0)
+		return 0;
+	if (a->listen_port != b->listen_port)
+		return 0;
+	if (strcmp_maybe_null(a->listen_path, b->listen_path) == 0)
+		return 0;
+	if (strcmp_maybe_null(a->connect_host, b->connect_host) == 0)
+		return 0;
+	if (a->connect_port != b->connect_port)
+		return 0;
+	if (strcmp_maybe_null(a->connect_path, b->connect_path) == 0)
+		return 0;
+	/* allocated_port and handle are not checked */
+	return 1;
+}
+
+/* returns 1 if process is already daemonized, 0 otherwise */
+int
+daemonized(void)
+{
+	int fd;
+
+	if ((fd = open(_PATH_TTY, O_RDONLY | O_NOCTTY)) >= 0) {
+		close(fd);
+		return 0;	/* have controlling terminal */
+	}
+	if (getppid() != 1)
+		return 0;	/* parent is not init */
+	if (getsid(0) != getpid())
+		return 0;	/* not session leader */
+	debug3("already daemonized");
+	return 1;
+}
+
+/*
+ * Splits 's' into an argument vector. Handles quoted string and basic
+ * escape characters (\\, \", \'). Caller must free the argument vector
+ * and its members.
+ */
+int
+argv_split(const char *s, int *argcp, char ***argvp, int terminate_on_comment)
+{
+	int r = SSH_ERR_INTERNAL_ERROR;
+	int argc = 0, quote, i, j;
+	char *arg, **argv = xcalloc(1, sizeof(*argv));
+
+	*argvp = NULL;
+	*argcp = 0;
+
+	for (i = 0; s[i] != '\0'; i++) {
+		/* Skip leading whitespace */
+		if (s[i] == ' ' || s[i] == '\t')
+			continue;
+		if (terminate_on_comment && s[i] == '#')
+			break;
+		/* Start of a token */
+		quote = 0;
+
+		argv = xreallocarray(argv, (argc + 2), sizeof(*argv));
+		arg = argv[argc++] = xcalloc(1, strlen(s + i) + 1);
+		argv[argc] = NULL;
+
+		/* Copy the token in, removing escapes */
+		for (j = 0; s[i] != '\0'; i++) {
+			if (s[i] == '\\') {
+				if (s[i + 1] == '\'' ||
+				    s[i + 1] == '\"' ||
+				    s[i + 1] == '\\' ||
+				    (quote == 0 && s[i + 1] == ' ')) {
+					i++; /* Skip '\' */
+					arg[j++] = s[i];
+				} else {
+					/* Unrecognised escape */
+					arg[j++] = s[i];
+				}
+			} else if (quote == 0 && (s[i] == ' ' || s[i] == '\t'))
+				break; /* done */
+			else if (quote == 0 && (s[i] == '\"' || s[i] == '\''))
+				quote = s[i]; /* quote start */
+			else if (quote != 0 && s[i] == quote)
+				quote = 0; /* quote end */
+			else
+				arg[j++] = s[i];
+		}
+		if (s[i] == '\0') {
+			if (quote != 0) {
+				/* Ran out of string looking for close quote */
+				r = SSH_ERR_INVALID_FORMAT;
+				goto out;
+			}
+			break;
+		}
+	}
+	/* Success */
+	*argcp = argc;
+	*argvp = argv;
+	argc = 0;
+	argv = NULL;
+	r = 0;
+ out:
+	if (argc != 0 && argv != NULL) {
+		for (i = 0; i < argc; i++)
+			free(argv[i]);
+		free(argv);
+	}
+	return r;
+}
+
+/*
+ * Reassemble an argument vector into a string, quoting and escaping as
+ * necessary. Caller must free returned string.
+ */
+char *
+argv_assemble(int argc, char **argv)
+{
+	int i, j, ws, r;
+	char c, *ret;
+	struct sshbuf *buf, *arg;
+
+	if ((buf = sshbuf_new()) == NULL || (arg = sshbuf_new()) == NULL)
+		fatal_f("sshbuf_new failed");
+
+	for (i = 0; i < argc; i++) {
+		ws = 0;
+		sshbuf_reset(arg);
+		for (j = 0; argv[i][j] != '\0'; j++) {
+			r = 0;
+			c = argv[i][j];
+			switch (c) {
+			case ' ':
+			case '\t':
+				ws = 1;
+				r = sshbuf_put_u8(arg, c);
+				break;
+			case '\\':
+			case '\'':
+			case '"':
+				if ((r = sshbuf_put_u8(arg, '\\')) != 0)
+					break;
+				/* FALLTHROUGH */
+			default:
+				r = sshbuf_put_u8(arg, c);
+				break;
+			}
+			if (r != 0)
+				fatal_fr(r, "sshbuf_put_u8");
+		}
+		if ((i != 0 && (r = sshbuf_put_u8(buf, ' ')) != 0) ||
+		    (ws != 0 && (r = sshbuf_put_u8(buf, '"')) != 0) ||
+		    (r = sshbuf_putb(buf, arg)) != 0 ||
+		    (ws != 0 && (r = sshbuf_put_u8(buf, '"')) != 0))
+			fatal_fr(r, "assemble");
+	}
+	if ((ret = malloc(sshbuf_len(buf) + 1)) == NULL)
+		fatal_f("malloc failed");
+	memcpy(ret, sshbuf_ptr(buf), sshbuf_len(buf));
+	ret[sshbuf_len(buf)] = '\0';
+	sshbuf_free(buf);
+	sshbuf_free(arg);
+	return ret;
+}
+
+char *
+argv_next(int *argcp, char ***argvp)
+{
+	char *ret = (*argvp)[0];
+
+	if (*argcp > 0 && ret != NULL) {
+		(*argcp)--;
+		(*argvp)++;
+	}
+	return ret;
+}
+
+void
+argv_consume(int *argcp)
+{
+	*argcp = 0;
+}
+
+void
+argv_free(char **av, int ac)
+{
+	int i;
+
+	if (av == NULL)
+		return;
+	for (i = 0; i < ac; i++)
+		free(av[i]);
+	free(av);
+}
+
+/* Returns 0 if pid exited cleanly, non-zero otherwise */
+int
+exited_cleanly(pid_t pid, const char *tag, const char *cmd, int quiet)
+{
+	int status;
+
+	while (waitpid(pid, &status, 0) == -1) {
+		if (errno != EINTR) {
+			error("%s waitpid: %s", tag, strerror(errno));
+			return -1;
+		}
+	}
+	if (WIFSIGNALED(status)) {
+		error("%s %s exited on signal %d", tag, cmd, WTERMSIG(status));
+		return -1;
+	} else if (WEXITSTATUS(status) != 0) {
+		do_log2(quiet ? SYSLOG_LEVEL_DEBUG1 : SYSLOG_LEVEL_INFO,
+		    "%s %s failed, status %d", tag, cmd, WEXITSTATUS(status));
+		return -1;
+	}
+	return 0;
+}
+
+/*
+ * Check a given path for security. This is defined as all components
+ * of the path to the file must be owned by either the owner of
+ * of the file or root and no directories must be group or world writable.
+ *
+ * XXX Should any specific check be done for sym links ?
+ *
+ * Takes a file name, its stat information (preferably from fstat() to
+ * avoid races), the uid of the expected owner, their home directory and an
+ * error buffer plus max size as arguments.
+ *
+ * Returns 0 on success and -1 on failure
+ */
+int
+safe_path(const char *name, struct stat *stp, const char *pw_dir,
+    uid_t uid, char *err, size_t errlen)
+{
+	char buf[PATH_MAX], homedir[PATH_MAX];
+	char *cp;
+	int comparehome = 0;
+	struct stat st;
+
+	if (realpath(name, buf) == NULL) {
+		snprintf(err, errlen, "realpath %s failed: %s", name,
+		    strerror(errno));
+		return -1;
+	}
+	if (pw_dir != NULL && realpath(pw_dir, homedir) != NULL)
+		comparehome = 1;
+
+	if (!S_ISREG(stp->st_mode)) {
+		snprintf(err, errlen, "%s is not a regular file", buf);
+		return -1;
+	}
+	if ((!platform_sys_dir_uid(stp->st_uid) && stp->st_uid != uid) ||
+	    (stp->st_mode & 022) != 0) {
+		snprintf(err, errlen, "bad ownership or modes for file %s",
+		    buf);
+		return -1;
+	}
+
+	/* for each component of the canonical path, walking upwards */
+	for (;;) {
+		if ((cp = dirname(buf)) == NULL) {
+			snprintf(err, errlen, "dirname() failed");
+			return -1;
+		}
+		strlcpy(buf, cp, sizeof(buf));
+
+		if (stat(buf, &st) == -1 ||
+		    (!platform_sys_dir_uid(st.st_uid) && st.st_uid != uid) ||
+		    (st.st_mode & 022) != 0) {
+			snprintf(err, errlen,
+			    "bad ownership or modes for directory %s", buf);
+			return -1;
+		}
+
+		/* If are past the homedir then we can stop */
+		if (comparehome && strcmp(homedir, buf) == 0)
+			break;
+
+		/*
+		 * dirname should always complete with a "/" path,
+		 * but we can be paranoid and check for "." too
+		 */
+		if ((strcmp("/", buf) == 0) || (strcmp(".", buf) == 0))
+			break;
+	}
+	return 0;
+}
+
+/*
+ * Version of safe_path() that accepts an open file descriptor to
+ * avoid races.
+ *
+ * Returns 0 on success and -1 on failure
+ */
+int
+safe_path_fd(int fd, const char *file, struct passwd *pw,
+    char *err, size_t errlen)
+{
+	struct stat st;
+
+	/* check the open file to avoid races */
+	if (fstat(fd, &st) == -1) {
+		snprintf(err, errlen, "cannot stat file %s: %s",
+		    file, strerror(errno));
+		return -1;
+	}
+	return safe_path(file, &st, pw->pw_dir, pw->pw_uid, err, errlen);
+}
+
+/*
+ * Sets the value of the given variable in the environment.  If the variable
+ * already exists, its value is overridden.
+ */
+void
+child_set_env(char ***envp, u_int *envsizep, const char *name,
+	const char *value)
+{
+	char **env;
+	u_int envsize;
+	u_int i, namelen;
+
+	if (strchr(name, '=') != NULL) {
+		error("Invalid environment variable \"%.100s\"", name);
+		return;
+	}
+
+	/*
+	 * If we're passed an uninitialized list, allocate a single null
+	 * entry before continuing.
+	 */
+	if (*envp == NULL && *envsizep == 0) {
+		*envp = xmalloc(sizeof(char *));
+		*envp[0] = NULL;
+		*envsizep = 1;
+	}
+
+	/*
+	 * Find the slot where the value should be stored.  If the variable
+	 * already exists, we reuse the slot; otherwise we append a new slot
+	 * at the end of the array, expanding if necessary.
+	 */
+	env = *envp;
+	namelen = strlen(name);
+	for (i = 0; env[i]; i++)
+		if (strncmp(env[i], name, namelen) == 0 && env[i][namelen] == '=')
+			break;
+	if (env[i]) {
+		/* Reuse the slot. */
+		free(env[i]);
+	} else {
+		/* New variable.  Expand if necessary. */
+		envsize = *envsizep;
+		if (i >= envsize - 1) {
+			if (envsize >= 1000)
+				fatal("child_set_env: too many env vars");
+			envsize += 50;
+			env = (*envp) = xreallocarray(env, envsize, sizeof(char *));
+			*envsizep = envsize;
+		}
+		/* Need to set the NULL pointer at end of array beyond the new slot. */
+		env[i + 1] = NULL;
+	}
+
+	/* Allocate space and format the variable in the appropriate slot. */
+	/* XXX xasprintf */
+	env[i] = xmalloc(strlen(name) + 1 + strlen(value) + 1);
+	snprintf(env[i], strlen(name) + 1 + strlen(value) + 1, "%s=%s", name, value);
+}
+
+/*
+ * Check and optionally lowercase a domain name, also removes trailing '.'
+ * Returns 1 on success and 0 on failure, storing an error message in errstr.
+ */
+int
+valid_domain(char *name, int makelower, const char **errstr)
+{
+	size_t i, l = strlen(name);
+	u_char c, last = '\0';
+	static char errbuf[256];
+
+	if (l == 0) {
+		strlcpy(errbuf, "empty domain name", sizeof(errbuf));
+		goto bad;
+	}
+	if (!isalpha((u_char)name[0]) && !isdigit((u_char)name[0])) {
+		snprintf(errbuf, sizeof(errbuf), "domain name \"%.100s\" "
+		    "starts with invalid character", name);
+		goto bad;
+	}
+	for (i = 0; i < l; i++) {
+		c = tolower((u_char)name[i]);
+		if (makelower)
+			name[i] = (char)c;
+		if (last == '.' && c == '.') {
+			snprintf(errbuf, sizeof(errbuf), "domain name "
+			    "\"%.100s\" contains consecutive separators", name);
+			goto bad;
+		}
+		if (c != '.' && c != '-' && !isalnum(c) &&
+		    c != '_') /* technically invalid, but common */ {
+			snprintf(errbuf, sizeof(errbuf), "domain name "
+			    "\"%.100s\" contains invalid characters", name);
+			goto bad;
+		}
+		last = c;
+	}
+	if (name[l - 1] == '.')
+		name[l - 1] = '\0';
+	if (errstr != NULL)
+		*errstr = NULL;
+	return 1;
+bad:
+	if (errstr != NULL)
+		*errstr = errbuf;
+	return 0;
+}
+
+/*
+ * Verify that a environment variable name (not including initial '$') is
+ * valid; consisting of one or more alphanumeric or underscore characters only.
+ * Returns 1 on valid, 0 otherwise.
+ */
+int
+valid_env_name(const char *name)
+{
+	const char *cp;
+
+	if (name[0] == '\0')
+		return 0;
+	for (cp = name; *cp != '\0'; cp++) {
+		if (!isalnum((u_char)*cp) && *cp != '_')
+			return 0;
+	}
+	return 1;
+}
+
+const char *
+atoi_err(const char *nptr, int *val)
+{
+	const char *errstr = NULL;
+	long long num;
+
+	if (nptr == NULL || *nptr == '\0')
+		return "missing";
+	num = strtonum(nptr, 0, INT_MAX, &errstr);
+	if (errstr == NULL)
+		*val = (int)num;
+	return errstr;
+}
+
+int
+parse_absolute_time(const char *s, uint64_t *tp)
+{
+	struct tm tm;
+	time_t tt;
+	char buf[32], *fmt;
+	const char *cp;
+	size_t l;
+	int is_utc = 0;
+
+	*tp = 0;
+
+	l = strlen(s);
+	if (l > 1 && strcasecmp(s + l - 1, "Z") == 0) {
+		is_utc = 1;
+		l--;
+	} else if (l > 3 && strcasecmp(s + l - 3, "UTC") == 0) {
+		is_utc = 1;
+		l -= 3;
+	}
+	/*
+	 * POSIX strptime says "The application shall ensure that there
+	 * is white-space or other non-alphanumeric characters between
+	 * any two conversion specifications" so arrange things this way.
+	 */
+	switch (l) {
+	case 8: /* YYYYMMDD */
+		fmt = "%Y-%m-%d";
+		snprintf(buf, sizeof(buf), "%.4s-%.2s-%.2s", s, s + 4, s + 6);
+		break;
+	case 12: /* YYYYMMDDHHMM */
+		fmt = "%Y-%m-%dT%H:%M";
+		snprintf(buf, sizeof(buf), "%.4s-%.2s-%.2sT%.2s:%.2s",
+		    s, s + 4, s + 6, s + 8, s + 10);
+		break;
+	case 14: /* YYYYMMDDHHMMSS */
+		fmt = "%Y-%m-%dT%H:%M:%S";
+		snprintf(buf, sizeof(buf), "%.4s-%.2s-%.2sT%.2s:%.2s:%.2s",
+		    s, s + 4, s + 6, s + 8, s + 10, s + 12);
+		break;
+	default:
+		return SSH_ERR_INVALID_FORMAT;
+	}
+
+	memset(&tm, 0, sizeof(tm));
+	if ((cp = strptime(buf, fmt, &tm)) == NULL || *cp != '\0')
+		return SSH_ERR_INVALID_FORMAT;
+	if (is_utc) {
+		if ((tt = timegm(&tm)) < 0)
+			return SSH_ERR_INVALID_FORMAT;
+	} else {
+		if ((tt = mktime(&tm)) < 0)
+			return SSH_ERR_INVALID_FORMAT;
+	}
+	/* success */
+	*tp = (uint64_t)tt;
+	return 0;
+}
+
+/* On OpenBSD time_t is int64_t which is long long. */
+/* #define SSH_TIME_T_MAX LLONG_MAX */
+
+void
+format_absolute_time(uint64_t t, char *buf, size_t len)
+{
+	time_t tt = t > SSH_TIME_T_MAX ? SSH_TIME_T_MAX : t;
+	struct tm tm;
+
+	localtime_r(&tt, &tm);
+	strftime(buf, len, "%Y-%m-%dT%H:%M:%S", &tm);
+}
+
+/* check if path is absolute */
+int
+path_absolute(const char *path)
+{
+	return (*path == '/') ? 1 : 0;
+}
+
+void
+skip_space(char **cpp)
+{
+	char *cp;
+
+	for (cp = *cpp; *cp == ' ' || *cp == '\t'; cp++)
+		;
+	*cpp = cp;
+}
+
+/* authorized_key-style options parsing helpers */
+
+/*
+ * Match flag 'opt' in *optsp, and if allow_negate is set then also match
+ * 'no-opt'. Returns -1 if option not matched, 1 if option matches or 0
+ * if negated option matches.
+ * If the option or negated option matches, then *optsp is updated to
+ * point to the first character after the option.
+ */
+int
+opt_flag(const char *opt, int allow_negate, const char **optsp)
+{
+	size_t opt_len = strlen(opt);
+	const char *opts = *optsp;
+	int negate = 0;
+
+	if (allow_negate && strncasecmp(opts, "no-", 3) == 0) {
+		opts += 3;
+		negate = 1;
+	}
+	if (strncasecmp(opts, opt, opt_len) == 0) {
+		*optsp = opts + opt_len;
+		return negate ? 0 : 1;
+	}
+	return -1;
+}
+
+char *
+opt_dequote(const char **sp, const char **errstrp)
+{
+	const char *s = *sp;
+	char *ret;
+	size_t i;
+
+	*errstrp = NULL;
+	if (*s != '"') {
+		*errstrp = "missing start quote";
+		return NULL;
+	}
+	s++;
+	if ((ret = malloc(strlen((s)) + 1)) == NULL) {
+		*errstrp = "memory allocation failed";
+		return NULL;
+	}
+	for (i = 0; *s != '\0' && *s != '"';) {
+		if (s[0] == '\\' && s[1] == '"')
+			s++;
+		ret[i++] = *s++;
+	}
+	if (*s == '\0') {
+		*errstrp = "missing end quote";
+		free(ret);
+		return NULL;
+	}
+	ret[i] = '\0';
+	s++;
+	*sp = s;
+	return ret;
+}
+
+int
+opt_match(const char **opts, const char *term)
+{
+	if (strncasecmp((*opts), term, strlen(term)) == 0 &&
+	    (*opts)[strlen(term)] == '=') {
+		*opts += strlen(term) + 1;
+		return 1;
+	}
+	return 0;
+}
+
+void
+opt_array_append2(const char *file, const int line, const char *directive,
+    char ***array, int **iarray, u_int *lp, const char *s, int i)
+{
+
+	if (*lp >= INT_MAX)
+		fatal("%s line %d: Too many %s entries", file, line, directive);
+
+	if (iarray != NULL) {
+		*iarray = xrecallocarray(*iarray, *lp, *lp + 1,
+		    sizeof(**iarray));
+		(*iarray)[*lp] = i;
+	}
+
+	*array = xrecallocarray(*array, *lp, *lp + 1, sizeof(**array));
+	(*array)[*lp] = xstrdup(s);
+	(*lp)++;
+}
+
+void
+opt_array_append(const char *file, const int line, const char *directive,
+    char ***array, u_int *lp, const char *s)
+{
+	opt_array_append2(file, line, directive, array, NULL, lp, s, 0);
+}
+
+sshsig_t
+ssh_signal(int signum, sshsig_t handler)
+{
+	struct sigaction sa, osa;
+
+	/* mask all other signals while in handler */
+	memset(&sa, 0, sizeof(sa));
+	sa.sa_handler = handler;
+	sigfillset(&sa.sa_mask);
+#if defined(SA_RESTART) && !defined(NO_SA_RESTART)
+	if (signum != SIGALRM)
+		sa.sa_flags = SA_RESTART;
+#endif
+	if (sigaction(signum, &sa, &osa) == -1) {
+		debug3("sigaction(%s): %s", strsignal(signum), strerror(errno));
+		return SIG_ERR;
+	}
+	return osa.sa_handler;
+}
+
+int
+stdfd_devnull(int do_stdin, int do_stdout, int do_stderr)
+{
+	int devnull, ret = 0;
+
+	if ((devnull = open(_PATH_DEVNULL, O_RDWR)) == -1) {
+		error_f("open %s: %s", _PATH_DEVNULL,
+		    strerror(errno));
+		return -1;
+	}
+	if ((do_stdin && dup2(devnull, STDIN_FILENO) == -1) ||
+	    (do_stdout && dup2(devnull, STDOUT_FILENO) == -1) ||
+	    (do_stderr && dup2(devnull, STDERR_FILENO) == -1)) {
+		error_f("dup2: %s", strerror(errno));
+		ret = -1;
+	}
+	if (devnull > STDERR_FILENO)
+		close(devnull);
+	return ret;
+}
+
+/*
+ * Runs command in a subprocess with a minimal environment.
+ * Returns pid on success, 0 on failure.
+ * The child stdout and stderr maybe captured, left attached or sent to
+ * /dev/null depending on the contents of flags.
+ * "tag" is prepended to log messages.
+ * NB. "command" is only used for logging; the actual command executed is
+ * av[0].
+ */
+pid_t
+subprocess(const char *tag, const char *command,
+    int ac, char **av, FILE **child, u_int flags,
+    struct passwd *pw, privdrop_fn *drop_privs, privrestore_fn *restore_privs)
+{
+	FILE *f = NULL;
+	struct stat st;
+	int fd, devnull, p[2], i;
+	pid_t pid;
+	char *cp, errmsg[512];
+	u_int nenv = 0;
+	char **env = NULL;
+
+	/* If dropping privs, then must specify user and restore function */
+	if (drop_privs != NULL && (pw == NULL || restore_privs == NULL)) {
+		error("%s: inconsistent arguments", tag); /* XXX fatal? */
+		return 0;
+	}
+	if (pw == NULL && (pw = getpwuid(getuid())) == NULL) {
+		error("%s: no user for current uid", tag);
+		return 0;
+	}
+	if (child != NULL)
+		*child = NULL;
+
+	debug3_f("%s command \"%s\" running as %s (flags 0x%x)",
+	    tag, command, pw->pw_name, flags);
+
+	/* Check consistency */
+	if ((flags & SSH_SUBPROCESS_STDOUT_DISCARD) != 0 &&
+	    (flags & SSH_SUBPROCESS_STDOUT_CAPTURE) != 0) {
+		error_f("inconsistent flags");
+		return 0;
+	}
+	if (((flags & SSH_SUBPROCESS_STDOUT_CAPTURE) == 0) != (child == NULL)) {
+		error_f("inconsistent flags/output");
+		return 0;
+	}
+
+	/*
+	 * If executing an explicit binary, then verify the it exists
+	 * and appears safe-ish to execute
+	 */
+	if (!path_absolute(av[0])) {
+		error("%s path is not absolute", tag);
+		return 0;
+	}
+	if (drop_privs != NULL)
+		drop_privs(pw);
+	if (stat(av[0], &st) == -1) {
+		error("Could not stat %s \"%s\": %s", tag,
+		    av[0], strerror(errno));
+		goto restore_return;
+	}
+	if ((flags & SSH_SUBPROCESS_UNSAFE_PATH) == 0 &&
+	    safe_path(av[0], &st, NULL, 0, errmsg, sizeof(errmsg)) != 0) {
+		error("Unsafe %s \"%s\": %s", tag, av[0], errmsg);
+		goto restore_return;
+	}
+	/* Prepare to keep the child's stdout if requested */
+	if (pipe(p) == -1) {
+		error("%s: pipe: %s", tag, strerror(errno));
+ restore_return:
+		if (restore_privs != NULL)
+			restore_privs();
+		return 0;
+	}
+	if (restore_privs != NULL)
+		restore_privs();
+
+	switch ((pid = fork())) {
+	case -1: /* error */
+		error("%s: fork: %s", tag, strerror(errno));
+		close(p[0]);
+		close(p[1]);
+		return 0;
+	case 0: /* child */
+		/* Prepare a minimal environment for the child. */
+		if ((flags & SSH_SUBPROCESS_PRESERVE_ENV) == 0) {
+			nenv = 5;
+			env = xcalloc(sizeof(*env), nenv);
+			child_set_env(&env, &nenv, "PATH", _PATH_STDPATH);
+			child_set_env(&env, &nenv, "USER", pw->pw_name);
+			child_set_env(&env, &nenv, "LOGNAME", pw->pw_name);
+			child_set_env(&env, &nenv, "HOME", pw->pw_dir);
+			if ((cp = getenv("LANG")) != NULL)
+				child_set_env(&env, &nenv, "LANG", cp);
+		}
+
+		for (i = 1; i < NSIG; i++)
+			ssh_signal(i, SIG_DFL);
+
+		if ((devnull = open(_PATH_DEVNULL, O_RDWR)) == -1) {
+			error("%s: open %s: %s", tag, _PATH_DEVNULL,
+			    strerror(errno));
+			_exit(1);
+		}
+		if (dup2(devnull, STDIN_FILENO) == -1) {
+			error("%s: dup2: %s", tag, strerror(errno));
+			_exit(1);
+		}
+
+		/* Set up stdout as requested; leave stderr in place for now. */
+		fd = -1;
+		if ((flags & SSH_SUBPROCESS_STDOUT_CAPTURE) != 0)
+			fd = p[1];
+		else if ((flags & SSH_SUBPROCESS_STDOUT_DISCARD) != 0)
+			fd = devnull;
+		if (fd != -1 && dup2(fd, STDOUT_FILENO) == -1) {
+			error("%s: dup2: %s", tag, strerror(errno));
+			_exit(1);
+		}
+		closefrom(STDERR_FILENO + 1);
+
+		if (geteuid() == 0 &&
+		    initgroups(pw->pw_name, pw->pw_gid) == -1) {
+			error("%s: initgroups(%s, %u): %s", tag,
+			    pw->pw_name, (u_int)pw->pw_gid, strerror(errno));
+			_exit(1);
+		}
+		if (setresgid(pw->pw_gid, pw->pw_gid, pw->pw_gid) == -1) {
+			error("%s: setresgid %u: %s", tag, (u_int)pw->pw_gid,
+			    strerror(errno));
+			_exit(1);
+		}
+		if (setresuid(pw->pw_uid, pw->pw_uid, pw->pw_uid) == -1) {
+			error("%s: setresuid %u: %s", tag, (u_int)pw->pw_uid,
+			    strerror(errno));
+			_exit(1);
+		}
+		/* stdin is pointed to /dev/null at this point */
+		if ((flags & SSH_SUBPROCESS_STDOUT_DISCARD) != 0 &&
+		    dup2(STDIN_FILENO, STDERR_FILENO) == -1) {
+			error("%s: dup2: %s", tag, strerror(errno));
+			_exit(1);
+		}
+		if (env != NULL)
+			execve(av[0], av, env);
+		else
+			execv(av[0], av);
+		error("%s %s \"%s\": %s", tag, env == NULL ? "execv" : "execve",
+		    command, strerror(errno));
+		_exit(127);
+	default: /* parent */
+		break;
+	}
+
+	close(p[1]);
+	if ((flags & SSH_SUBPROCESS_STDOUT_CAPTURE) == 0)
+		close(p[0]);
+	else if ((f = fdopen(p[0], "r")) == NULL) {
+		error("%s: fdopen: %s", tag, strerror(errno));
+		close(p[0]);
+		/* Don't leave zombie child */
+		kill(pid, SIGTERM);
+		while (waitpid(pid, NULL, 0) == -1 && errno == EINTR)
+			;
+		return 0;
+	}
+	/* Success */
+	debug3_f("%s pid %ld", tag, (long)pid);
+	if (child != NULL)
+		*child = f;
+	return pid;
+}
+
+const char *
+lookup_env_in_list(const char *env, char * const *envs, size_t nenvs)
+{
+	size_t i, envlen;
+
+	envlen = strlen(env);
+	for (i = 0; i < nenvs; i++) {
+		if (strncmp(envs[i], env, envlen) == 0 &&
+		    envs[i][envlen] == '=') {
+			return envs[i] + envlen + 1;
+		}
+	}
+	return NULL;
+}
+
+const char *
+lookup_setenv_in_list(const char *env, char * const *envs, size_t nenvs)
+{
+	char *name, *cp;
+	const char *ret;
+
+	name = xstrdup(env);
+	if ((cp = strchr(name, '=')) == NULL) {
+		free(name);
+		return NULL; /* not env=val */
+	}
+	*cp = '\0';
+	ret = lookup_env_in_list(name, envs, nenvs);
+	free(name);
+	return ret;
+}
+
+/*
+ * Helpers for managing poll(2)/ppoll(2) timeouts
+ * Will remember the earliest deadline and return it for use in poll/ppoll.
+ */
+
+/* Initialise a poll/ppoll timeout with an indefinite deadline */
+void
+ptimeout_init(struct timespec *pt)
+{
+	/*
+	 * Deliberately invalid for ppoll(2).
+	 * Will be converted to NULL in ptimeout_get_tspec() later.
+	 */
+	pt->tv_sec = -1;
+	pt->tv_nsec = 0;
+}
+
+/* Specify a poll/ppoll deadline of at most 'sec' seconds */
+void
+ptimeout_deadline_sec(struct timespec *pt, long sec)
+{
+	if (pt->tv_sec == -1 || pt->tv_sec >= sec) {
+		pt->tv_sec = sec;
+		pt->tv_nsec = 0;
+	}
+}
+
+/* Specify a poll/ppoll deadline of at most 'p' (timespec) */
+static void
+ptimeout_deadline_tsp(struct timespec *pt, struct timespec *p)
+{
+	if (pt->tv_sec == -1 || timespeccmp(pt, p, >=))
+		*pt = *p;
+}
+
+/* Specify a poll/ppoll deadline of at most 'ms' milliseconds */
+void
+ptimeout_deadline_ms(struct timespec *pt, long ms)
+{
+	struct timespec p;
+
+	p.tv_sec = ms / 1000;
+	p.tv_nsec = (ms % 1000) * 1000000;
+	ptimeout_deadline_tsp(pt, &p);
+}
+
+/* Specify a poll/ppoll deadline at wall clock monotime 'when' */
+void
+ptimeout_deadline_monotime(struct timespec *pt, time_t when)
+{
+	struct timespec now, t;
+
+	t.tv_sec = when;
+	t.tv_nsec = 0;
+	monotime_ts(&now);
+
+	if (timespeccmp(&now, &t, >=))
+		ptimeout_deadline_sec(pt, 0);
+	else {
+		timespecsub(&t, &now, &t);
+		ptimeout_deadline_tsp(pt, &t);
+	}
+}
+
+/* Get a poll(2) timeout value in milliseconds */
+int
+ptimeout_get_ms(struct timespec *pt)
+{
+	if (pt->tv_sec == -1)
+		return -1;
+	if (pt->tv_sec >= (INT_MAX - (pt->tv_nsec / 1000000)) / 1000)
+		return INT_MAX;
+	return (pt->tv_sec * 1000) + (pt->tv_nsec / 1000000);
+}
+
+/* Get a ppoll(2) timeout value as a timespec pointer */
+struct timespec *
+ptimeout_get_tsp(struct timespec *pt)
+{
+	return pt->tv_sec == -1 ? NULL : pt;
+}
+
+/* Returns non-zero if a timeout has been set (i.e. is not indefinite) */
+int
+ptimeout_isset(struct timespec *pt)
+{
+	return pt->tv_sec != -1;
+}