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-rw-r--r--misc.c2417
1 files changed, 2417 insertions, 0 deletions
diff --git a/misc.c b/misc.c
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index 0000000..4623b57
--- /dev/null
+++ b/misc.c
@@ -0,0 +1,2417 @@
+/* $OpenBSD: misc.c,v 1.153 2020/06/26 05:16:38 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>
+#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;
+
+}
+
+/* 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
+}
+
+/*
+ * 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;
+
+ monotime_tv(&t_start);
+ pfd.fd = fd;
+ pfd.events = events;
+ for (; *timeoutp >= 0;) {
+ 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);
+#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.
+ */
+long
+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 == LONG_MIN || secs == LONG_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 >= LONG_MAX / multiplier)
+ return -1;
+ secs *= multiplier;
+ if (total >= LONG_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;
+}
+
+char *
+hpdelim(char **cp)
+{
+ return hpdelim2(cp, NULL);
+}
+
+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("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 = 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("replacearg: argument too long");
+
+ if (which >= args->num)
+ fatal("replacearg: 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->list != NULL) {
+ 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*.
+ */
+char *
+tilde_expand_filename(const char *filename, uid_t uid)
+{
+ const char *path, *sep;
+ char user[128], *ret;
+ 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 %ld", (long)uid);
+
+ /* Make sure directory has a trailing '/' */
+ len = strlen(pw->pw_dir);
+ if (len == 0 || pw->pw_dir[len - 1] != '/')
+ sep = "/";
+ else
+ sep = "";
+
+ /* Skip leading '/' from specified path */
+ if (path != NULL)
+ filename = path + 1;
+
+ if (xasprintf(&ret, "%s%s%s", pw->pw_dir, sep, filename) >= PATH_MAX)
+ fatal("tilde_expand_filename: Path too long");
+
+ 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("%s: sshbuf_new failed", __func__);
+ if (parseerror == NULL)
+ fatal("%s: null parseerror arg", __func__);
+ *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("%s: NULL replacement for token %s", __func__, keys[num_keys].key);
+ }
+ if (num_keys == EXPAND_MAX_KEYS && va_arg(ap, char *) != NULL)
+ fatal("%s: too many keys", __func__);
+ if (num_keys == 0)
+ fatal("%s: percent expansion without token list",
+ __func__);
+ }
+
+ /* 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("%s: environment variable '%s' missing "
+ "closing '}'", __func__, string);
+ goto out;
+ }
+ len = varend - string;
+ if (len == 0) {
+ error("%s: zero-length environment variable",
+ __func__);
+ goto out;
+ }
+ var = xmalloc(len + 1);
+ (void)strlcpy(var, string, len + 1);
+ if ((val = getenv(var)) == NULL) {
+ error("%s: env var ${%s} has no value",
+ __func__, var);
+ missingvar = 1;
+ } else {
+ debug3("%s: expand ${%s} -> '%s'", __func__,
+ var, val);
+ if ((r = sshbuf_put(buf, val, strlen(val))) !=0)
+ fatal("%s: sshbuf_put: %s", __func__,
+ ssh_err(r));
+ }
+ 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("%s: sshbuf_put_u8: %s",
+ __func__, ssh_err(r));
+ }
+ continue;
+ }
+ string++;
+ /* %% case */
+ if (*string == '%')
+ goto append;
+ if (*string == '\0') {
+ error("%s: invalid format", __func__);
+ 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("%s: sshbuf_put: %s",
+ __func__, ssh_err(r));
+ }
+ break;
+ }
+ }
+ if (i >= num_keys) {
+ error("%s: unknown key %%%c", __func__, *string);
+ goto out;
+ }
+ }
+ if (!missingvar && (ret = sshbuf_dup_string(buf)) == NULL)
+ fatal("%s: sshbuf_dup_string failed", __func__);
+ *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("%s failed", __func__);
+ 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("%s failed", __func__);
+ 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("%s: invalid tunnel %u", __func__, tun);
+ return -1;
+ }
+
+ if (fd == -1) {
+ debug("%s: %s open: %s", __func__, name, strerror(errno));
+ return -1;
+ }
+
+ debug("%s: %s mode %d fd %d", __func__, 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("%s: get interface %s flags: %s", __func__,
+ 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("%s: activate interface %s: %s", __func__,
+ 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_timeval(struct timeval *tv, int ms)
+{
+ if (ms < 0)
+ ms = 0;
+ tv->tv_sec = ms / 1000;
+ tv->tv_usec = (ms % 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("%s: template string too short", __func__);
+}
+
+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("%s: path \"%s\" too long for Unix domain socket",
+ __func__, path);
+ errno = ENAMETOOLONG;
+ return -1;
+ }
+
+ sock = socket(PF_UNIX, SOCK_STREAM, 0);
+ if (sock == -1) {
+ saved_errno = errno;
+ error("%s: socket: %.100s", __func__, 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("%s: cannot bind to path %s: %s",
+ __func__, path, strerror(errno));
+ close(sock);
+ errno = saved_errno;
+ return -1;
+ }
+ if (listen(sock, backlog) == -1) {
+ saved_errno = errno;
+ error("%s: cannot listen on path %s: %s",
+ __func__, 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 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;
+
+ /* Start of a token */
+ quote = 0;
+ if (s[i] == '\\' &&
+ (s[i + 1] == '\'' || s[i + 1] == '\"' || s[i + 1] == '\\'))
+ i++;
+ else if (s[i] == '\'' || s[i] == '"')
+ quote = s[i++];
+
+ 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] == '\\') {
+ 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] == quote)
+ break; /* done */
+ 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("%s: sshbuf_new failed", __func__);
+
+ 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("%s: sshbuf_put_u8: %s",
+ __func__, ssh_err(r));
+ }
+ 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("%s: buffer error: %s", __func__, ssh_err(r));
+ }
+ if ((ret = malloc(sshbuf_len(buf) + 1)) == NULL)
+ fatal("%s: malloc failed", __func__);
+ memcpy(ret, sshbuf_ptr(buf), sshbuf_len(buf));
+ ret[sshbuf_len(buf)] = '\0';
+ sshbuf_free(buf);
+ sshbuf_free(arg);
+ return ret;
+}
+
+/* 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;
+
+ *tp = 0;
+
+ /*
+ * 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 (strlen(s)) {
+ 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 (strptime(buf, fmt, &tm) == NULL)
+ return SSH_ERR_INVALID_FORMAT;
+ if ((tt = mktime(&tm)) < 0)
+ return SSH_ERR_INVALID_FORMAT;
+ /* success */
+ *tp = (uint64_t)tt;
+ return 0;
+}
+
+void
+format_absolute_time(uint64_t t, char *buf, size_t len)
+{
+ time_t tt = t > INT_MAX ? INT_MAX : t; /* XXX revisit in 2038 :P */
+ 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;
+}
+
+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;
+}