#include <sys/cdefs.h>
__RCSID("$NetBSD: netcat.c,v 1.9 2026/03/03 03:14:41 kre Exp $");
#include <sys/types.h>
#include <sys/socket.h>
#include <sys/uio.h>
#include <sys/un.h>
#include <netinet/in.h>
#include <netinet/tcp.h>
#include <netinet/ip.h>
#include <arpa/telnet.h>
#include <ctype.h>
#include <err.h>
#include <errno.h>
#include <limits.h>
#include <netdb.h>
#include <poll.h>
#include <signal.h>
#include <stdarg.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <time.h>
#include <unistd.h>
#ifdef CRYPTO
#include <tls.h>
#else
#define TLS_WANT_POLLIN -2
#define TLS_WANT_POLLOUT -2
#endif
#include "atomicio.h"
#ifdef __NetBSD__
#define accept4(a, b, c, d) paccept((a), (b), (c), NULL, (d))
#endif
#define PORT_MAX 65535
#define UNIX_DG_TMP_SOCKET_SIZE 19
#define POLL_STDIN 0
#define POLL_NETOUT 1
#define POLL_NETIN 2
#define POLL_STDOUT 3
#define BUFSIZE 16384
#define DEFAULT_CA_FILE "/etc/ssl/cert.pem"
#define TLS_ALL (1 << 1)
#define TLS_NOVERIFY (1 << 2)
#define TLS_NONAME (1 << 3)
#define TLS_CCERT (1 << 4)
#define TLS_MUSTSTAPLE (1 << 5)
int dflag;
int Fflag;
unsigned int iflag;
int kflag;
int lflag;
int Nflag;
int nflag;
char *Pflag;
char *pflag;
int rflag;
char *sflag;
int tflag;
int uflag;
int vflag;
int xflag;
int zflag;
int Dflag;
int Iflag;
int Oflag;
int Sflag;
int Tflag = -1;
#ifdef __OpenBSD__
int rtableid = -1;
#endif
intmax_t maxsend, maxrecv;
#ifdef CRYPTO
int usetls;
char *Cflag;
char *Kflag;
char *oflag;
const char *Rflag = DEFAULT_CA_FILE;
int tls_cachanged;
int TLSopt;
char *tls_expectname;
char *tls_expecthash;
#endif
int timeout = -1;
int family = AF_UNSPEC;
char *portlist[PORT_MAX+1];
char *unix_dg_tmp_socket;
int ttl = -1;
int minttl = -1;
void atelnet(int, unsigned char *, unsigned int);
void build_ports(char *);
static void help(void) __dead;
int local_listen(char *, char *, struct addrinfo);
struct tls;
void readwrite(int, struct tls *);
void fdpass(int nfd) __dead;
int remote_connect(const char *, const char *, struct addrinfo);
int timeout_connect(int, const struct sockaddr *, socklen_t);
int socks_connect(const char *, const char *, struct addrinfo,
const char *, const char *, struct addrinfo, int, const char *);
int udptest(int);
int unix_bind(char *, int);
int unix_connect(char *);
int unix_listen(char *);
void set_common_sockopts(int, int);
int map_tos(char *, int *);
int map_tls(char *, int *);
void report_connect(const struct sockaddr *, socklen_t, char *);
void report_tls(struct tls *tls_ctx, char * host, char *tlsexpectname);
void usage(int);
ssize_t drainbuf(int, unsigned char *, size_t *, struct tls *);
ssize_t fillbuf(int, unsigned char *, size_t *, struct tls *);
#ifdef CRYPTO
void tls_setup_client(struct tls *, int, char *);
struct tls *tls_setup_server(struct tls *, int, char *);
#endif
int
main(int argc, char *argv[])
{
int ch, s = -1, ret, socksv;
char *host, *uport;
struct addrinfo hints;
struct servent *sv;
socklen_t len;
struct sockaddr_storage cliaddr;
char *proxy = NULL, *proxyport = NULL;
int errnum;
struct addrinfo proxyhints;
char unix_dg_tmp_socket_buf[UNIX_DG_TMP_SOCKET_SIZE];
#ifdef CRYPTO
struct tls_config *tls_cfg = NULL;
struct tls *tls_ctx = NULL;
#endif
ret = 1;
socksv = 5;
host = NULL;
uport = NULL;
sv = NULL;
signal(SIGPIPE, SIG_IGN);
while ((ch = getopt(argc, argv,
#ifdef CRYPTO
"46C:cDdE:e:FH:hI:i:K:klM:m:NnO:o:P:p:R:rSs:T:tUuvw:X:x:z"
#else
"46DdE:FhI:i:klM:m:NnO:P:p:rSs:tUuvw:X:x:z"
#endif
#ifdef __OpenBSD__
"V:"
#endif
)) != -1) {
switch (ch) {
case '4':
family = AF_INET;
break;
case '6':
family = AF_INET6;
break;
case 'U':
family = AF_UNIX;
break;
case 'X':
if (strcasecmp(optarg, "connect") == 0)
socksv = -1;
else if (strcmp(optarg, "4") == 0)
socksv = 4;
else if (strcmp(optarg, "5") == 0)
socksv = 5;
else
errx(1, "unsupported proxy protocol");
break;
#ifdef CRYPTO
case 'C':
Cflag = optarg;
break;
case 'c':
usetls = 1;
break;
#endif
case 'd':
dflag = 1;
break;
case 'E': {
char *ep;
maxsend = strtoi(optarg, &ep, 0, 0, UINT_MAX, &errnum);
if (errnum == ECANCELED)
maxsend = 0;
if ((errnum == ENOTSUP || errnum == ECANCELED) &&
*ep == '/' && (ep[1] == '\0' ||
isdigit(*(unsigned char *)(ep + 1)))) {
maxrecv = strtoi(ep + 1, &ep, 0, 0, UINT_MAX,
&errnum);
if (errnum == ECANCELED) {
maxrecv = 0;
if (*ep == '\0')
errnum = 0;
}
} else
maxrecv = maxsend;
if (errnum)
errc(1, errnum, "bad end specifier '%s'",
optarg);
break;
}
#ifdef CRYPTO
case 'e':
tls_expectname = optarg;
break;
#endif
case 'F':
Fflag = 1;
break;
#ifdef CRYPTO
case 'H':
tls_expecthash = optarg;
break;
#endif
case 'h':
help();
break;
case 'i':
iflag = strtoi(optarg, NULL, 0, 0, UINT_MAX, &errnum);
if (errnum)
errc(1, errnum, "bad interval `%s'", optarg);
break;
#ifdef CRYPTO
case 'K':
Kflag = optarg;
break;
#endif
case 'k':
kflag = 1;
break;
case 'l':
lflag = 1;
break;
case 'M':
ttl = strtoi(optarg, NULL, 0, 0, 255, &errnum);
if (errnum)
errc(1, errnum, "bad ttl `%s'", optarg);
break;
case 'm':
minttl = strtoi(optarg, NULL, 0, 0, 255, &errnum);
if (errnum)
errc(1, errnum, "bad minttl `%s'", optarg);
break;
case 'N':
Nflag = 1;
break;
case 'n':
nflag = 1;
break;
case 'P':
Pflag = optarg;
break;
case 'p':
pflag = optarg;
break;
#ifdef CRYPTO
case 'R':
tls_cachanged = 1;
Rflag = optarg;
break;
#endif
case 'r':
rflag = 1;
break;
case 's':
sflag = optarg;
break;
case 't':
tflag = 1;
break;
case 'u':
uflag = 1;
break;
#ifdef __OpenBSD__
case 'V':
rtableid = (int)strtoi(optarg, NULL, 0, 0, 255, &errnum);
if (errnum)
errc(1, errnum, "bad rtable `%s'", optarg);
break;
#endif
case 'v':
vflag = 1;
break;
case 'w':
timeout = strtoi(optarg, NULL, 0, 0, INT_MAX / 1000, &errnum);
if (errnum)
errc(1, errnum, "bad timeout `%s'", optarg);
timeout *= 1000;
break;
case 'x':
xflag = 1;
if ((proxy = strdup(optarg)) == NULL)
err(1, NULL);
break;
case 'z':
zflag = 1;
break;
case 'D':
Dflag = 1;
break;
case 'I':
Iflag = strtoi(optarg, NULL, 0, 1, 65536 << 14, &errnum);
if (errnum)
errc(1, errnum, "bad TCP receive window `%s'",
optarg);
break;
case 'O':
Oflag = strtoi(optarg, NULL, 0, 1, 65536 << 14, &errnum);
if (errnum)
errc(1, errnum, "bad TCP send window `%s'",
optarg);
break;
#ifdef CRYPTO
case 'o':
oflag = optarg;
break;
#endif
case 'S':
Sflag = 1;
break;
#ifdef CRYPTO
case 'T':
if (map_tos(optarg, &Tflag))
break;
if (map_tls(optarg, &TLSopt))
break;
Tflag = (int)strtoi(optarg, NULL, 0, 0, 255, &errnum);
if (errnum)
errc(1, errnum, "illegal tos/tls value `%s'",
optarg);
break;
#endif
default:
usage(1);
}
}
argc -= optind;
argv += optind;
#ifdef __OpenBSD__
if (rtableid >= 0)
if (setrtable(rtableid) == -1)
err(1, "setrtable");
if (family == AF_UNIX) {
if (pledge("stdio rpath wpath cpath tmppath unix", NULL) == -1)
err(1, "pledge");
} else if (Fflag) {
if (Pflag) {
if (pledge("stdio inet dns sendfd tty", NULL) == -1)
err(1, "pledge");
} else if (pledge("stdio inet dns sendfd", NULL) == -1)
err(1, "pledge");
} else if (Pflag) {
if (pledge("stdio inet dns tty", NULL) == -1)
err(1, "pledge");
} else if (usetls) {
if (pledge("stdio rpath inet dns", NULL) == -1)
err(1, "pledge");
} else if (pledge("stdio inet dns", NULL) == -1)
err(1, "pledge");
#endif
if (argv[0] && !argv[1] && family == AF_UNIX) {
host = argv[0];
uport = NULL;
} else if (argv[0] && !argv[1]) {
if (!lflag)
usage(1);
uport = argv[0];
host = NULL;
} else if (argv[0] && argv[1]) {
host = argv[0];
uport = argv[1];
} else
usage(1);
if (lflag && sflag)
errx(1, "cannot use -s and -l");
if (lflag && pflag)
errx(1, "cannot use -p and -l");
if (lflag && zflag)
errx(1, "cannot use -z and -l");
if (!lflag && kflag)
errx(1, "must use -l with -k");
if ((family == AF_UNIX) && Fflag)
errx(1, "cannot use -F and -U");
#ifdef CRYPTO
if (Fflag && usetls)
errx(1, "cannot use -c and -F");
if ((family == AF_UNIX) && usetls)
errx(1, "cannot use -c and -U");
if (uflag && usetls)
errx(1, "cannot use -c and -u");
if (TLSopt && !usetls)
errx(1, "you must specify -c to use TLS options");
if (Cflag && !usetls)
errx(1, "you must specify -c to use -C");
if (Kflag && !usetls)
errx(1, "you must specify -c to use -K");
if (oflag && !Cflag)
errx(1, "you must specify -C to use -o");
if (tls_cachanged && !usetls)
errx(1, "you must specify -c to use -R");
if (tls_expecthash && !usetls)
errx(1, "you must specify -c to use -H");
if (tls_expectname && !usetls)
errx(1, "you must specify -c to use -e");
#endif
if ((family == AF_UNIX) && uflag && !lflag) {
if (sflag) {
unix_dg_tmp_socket = sflag;
} else {
int fd;
snprintf(unix_dg_tmp_socket_buf,
sizeof(unix_dg_tmp_socket_buf),
"/tmp/%s.XXXXXXXXXX", getprogname());
if ((fd = mkstemp(unix_dg_tmp_socket_buf)) == -1)
err(1, "mktemp");
close(fd);
unix_dg_tmp_socket = unix_dg_tmp_socket_buf;
}
}
if (family != AF_UNIX) {
memset(&hints, 0, sizeof(struct addrinfo));
hints.ai_family = family;
hints.ai_socktype = uflag ? SOCK_DGRAM : SOCK_STREAM;
hints.ai_protocol = uflag ? IPPROTO_UDP : IPPROTO_TCP;
if (nflag)
hints.ai_flags |= AI_NUMERICHOST;
}
if (xflag) {
if (uflag)
errx(1, "no proxy support for UDP mode");
if (lflag)
errx(1, "no proxy support for listen");
if (family == AF_UNIX)
errx(1, "no proxy support for unix sockets");
if (sflag)
errx(1, "no proxy support for local source address");
if (*proxy == '[') {
++proxy;
proxyport = strchr(proxy, ']');
if (proxyport == NULL)
errx(1, "missing closing bracket in proxy");
*proxyport++ = '\0';
if (*proxyport == '\0')
proxyport = NULL;
else {
if (*proxyport == ':')
++proxyport;
else
errx(1, "garbage proxy port delimiter");
}
} else {
proxyport = strrchr(proxy, ':');
if (proxyport != NULL)
*proxyport++ = '\0';
}
memset(&proxyhints, 0, sizeof(struct addrinfo));
proxyhints.ai_family = family;
proxyhints.ai_socktype = SOCK_STREAM;
proxyhints.ai_protocol = IPPROTO_TCP;
if (nflag)
proxyhints.ai_flags |= AI_NUMERICHOST;
}
#ifdef CRYPTO
if (usetls) {
#if __OpenBSD__
if (Pflag) {
if (pledge("stdio inet dns tty rpath", NULL) == -1)
err(1, "pledge");
} else if (pledge("stdio inet dns rpath", NULL) == -1)
err(1, "pledge");
#endif
if (tls_init() == -1)
errx(1, "unable to initialize TLS");
if ((tls_cfg = tls_config_new()) == NULL)
errx(1, "unable to allocate TLS config");
if (Rflag && tls_config_set_ca_file(tls_cfg, Rflag) == -1)
errx(1, "%s", tls_config_error(tls_cfg));
if (Cflag && tls_config_set_cert_file(tls_cfg, Cflag) == -1)
errx(1, "%s", tls_config_error(tls_cfg));
if (Kflag && tls_config_set_key_file(tls_cfg, Kflag) == -1)
errx(1, "%s", tls_config_error(tls_cfg));
if (oflag && tls_config_set_ocsp_staple_file(tls_cfg, oflag) == -1)
errx(1, "%s", tls_config_error(tls_cfg));
if (TLSopt & TLS_ALL) {
if (tls_config_set_protocols(tls_cfg,
TLS_PROTOCOLS_ALL) != 0)
errx(1, "%s", tls_config_error(tls_cfg));
if (tls_config_set_ciphers(tls_cfg, "all") != 0)
errx(1, "%s", tls_config_error(tls_cfg));
}
if (!lflag && (TLSopt & TLS_CCERT))
errx(1, "clientcert is only valid with -l");
if (TLSopt & TLS_NONAME)
tls_config_insecure_noverifyname(tls_cfg);
if (TLSopt & TLS_NOVERIFY) {
if (tls_expecthash != NULL)
errx(1, "-H and -T noverify may not be used"
"together");
tls_config_insecure_noverifycert(tls_cfg);
}
if (TLSopt & TLS_MUSTSTAPLE)
tls_config_ocsp_require_stapling(tls_cfg);
#ifdef __OpenBSD__
if (Pflag) {
if (pledge("stdio inet dns tty", NULL) == -1)
err(1, "pledge");
} else if (pledge("stdio inet dns", NULL) == -1)
err(1, "pledge");
#endif
}
#endif
if (lflag) {
#ifdef CRYPTO
struct tls *tls_cctx = NULL;
#endif
int connfd;
ret = 0;
if (family == AF_UNIX) {
if (uflag)
s = unix_bind(host, 0);
else
s = unix_listen(host);
}
#ifdef CRYPTO
if (usetls) {
tls_config_verify_client_optional(tls_cfg);
if ((tls_ctx = tls_server()) == NULL)
errx(1, "tls server creation failed");
if (tls_configure(tls_ctx, tls_cfg) == -1)
errx(1, "tls configuration failed (%s)",
tls_error(tls_ctx));
}
#endif
for (;;) {
if (family != AF_UNIX)
s = local_listen(host, uport, hints);
if (s < 0)
err(1, NULL);
if (uflag && kflag)
readwrite(s, NULL);
else if (uflag && !kflag) {
int rv, plen;
char buf[16384];
struct sockaddr_storage z;
len = sizeof(z);
plen = 2048;
rv = recvfrom(s, buf, plen, MSG_PEEK,
(struct sockaddr *)&z, &len);
if (rv < 0)
err(1, "recvfrom");
rv = connect(s, (struct sockaddr *)&z, len);
if (rv < 0)
err(1, "connect");
if (vflag)
report_connect((struct sockaddr *)&z, len, NULL);
readwrite(s, NULL);
} else {
len = sizeof(cliaddr);
connfd = accept4(s, (struct sockaddr *)&cliaddr,
&len, SOCK_NONBLOCK);
if (connfd == -1) {
err(1, "accept");
}
if (vflag)
report_connect((struct sockaddr *)&cliaddr, len,
family == AF_UNIX ? host : NULL);
#ifdef CRYPTO
if ((usetls) &&
(tls_cctx = tls_setup_server(tls_ctx, connfd, host)))
readwrite(connfd, tls_cctx);
if (!usetls)
#endif
readwrite(connfd, NULL);
#ifdef CRYPTO
if (tls_cctx) {
int i;
do {
i = tls_close(tls_cctx);
} while (i == TLS_WANT_POLLIN ||
i == TLS_WANT_POLLOUT);
tls_free(tls_cctx);
tls_cctx = NULL;
}
#endif
close(connfd);
}
if (family != AF_UNIX)
close(s);
else if (uflag) {
if (connect(s, NULL, 0) < 0)
err(1, "connect");
}
if (!kflag)
break;
}
} else if (family == AF_UNIX) {
ret = 0;
if ((s = unix_connect(host)) > 0 && !zflag) {
readwrite(s, NULL);
close(s);
} else
ret = 1;
if (uflag)
unlink(unix_dg_tmp_socket);
exit(ret);
} else {
int i = 0;
build_ports(uport);
for (s = -1, i = 0; portlist[i] != NULL; i++) {
if (s != -1)
close(s);
#ifdef CRYPTO
if (usetls) {
if ((tls_ctx = tls_client()) == NULL)
errx(1, "tls client creation failed");
if (tls_configure(tls_ctx, tls_cfg) == -1)
errx(1, "tls configuration failed (%s)",
tls_error(tls_ctx));
}
#endif
if (xflag)
s = socks_connect(host, portlist[i], hints,
proxy, proxyport, proxyhints, socksv,
Pflag);
else
s = remote_connect(host, portlist[i], hints);
if (s == -1)
continue;
ret = 0;
if (vflag || zflag) {
if (uflag) {
if (udptest(s) == -1) {
ret = 1;
continue;
}
}
if (nflag)
sv = NULL;
else {
sv = getservbyport(
ntohs(atoi(portlist[i])),
uflag ? "udp" : "tcp");
}
fprintf(stderr,
"Connection to %s %s port [%s/%s] "
"succeeded!\n", host, portlist[i],
uflag ? "udp" : "tcp",
sv ? sv->s_name : "*");
}
if (Fflag)
fdpass(s);
else {
#ifdef CRYPTO
if (usetls)
tls_setup_client(tls_ctx, s, host);
if (!zflag)
readwrite(s, tls_ctx);
if (tls_ctx) {
int j;
do {
j = tls_close(tls_ctx);
} while (j == TLS_WANT_POLLIN ||
j == TLS_WANT_POLLOUT);
tls_free(tls_ctx);
tls_ctx = NULL;
}
#else
if (!zflag)
readwrite(s, NULL);
#endif
}
}
}
if (s != -1)
close(s);
#ifdef CRYPTO
tls_config_free(tls_cfg);
#endif
exit(ret);
}
int
unix_bind(char *path, int flags)
{
struct sockaddr_un s_un;
int s, save_errno;
if ((s = socket(AF_UNIX, flags | (uflag ? SOCK_DGRAM : SOCK_STREAM),
0)) < 0)
return (-1);
memset(&s_un, 0, sizeof(struct sockaddr_un));
s_un.sun_family = AF_UNIX;
if (strlcpy(s_un.sun_path, path, sizeof(s_un.sun_path)) >=
sizeof(s_un.sun_path)) {
close(s);
errno = ENAMETOOLONG;
return (-1);
}
if (bind(s, (struct sockaddr *)&s_un, sizeof(s_un)) < 0) {
save_errno = errno;
close(s);
errno = save_errno;
return (-1);
}
return (s);
}
#ifdef CRYPTO
void
tls_setup_client(struct tls *tls_ctx, int s, char *host)
{
int i;
if (tls_connect_socket(tls_ctx, s,
tls_expectname ? tls_expectname : host) == -1) {
errx(1, "tls connection failed (%s)",
tls_error(tls_ctx));
}
do {
if ((i = tls_handshake(tls_ctx)) == -1)
errx(1, "tls handshake failed (%s)",
tls_error(tls_ctx));
} while (i == TLS_WANT_POLLIN || i == TLS_WANT_POLLOUT);
if (vflag)
report_tls(tls_ctx, host, tls_expectname);
if (tls_expecthash && tls_peer_cert_hash(tls_ctx) &&
strcmp(tls_expecthash, tls_peer_cert_hash(tls_ctx)) != 0)
errx(1, "peer certificate is not %s", tls_expecthash);
}
struct tls *
tls_setup_server(struct tls *tls_ctx, int connfd, char *host)
{
struct tls *tls_cctx;
if (tls_accept_socket(tls_ctx, &tls_cctx,
connfd) == -1) {
warnx("tls accept failed (%s)",
tls_error(tls_ctx));
tls_cctx = NULL;
} else {
int i;
do {
if ((i = tls_handshake(tls_cctx)) == -1)
warnx("tls handshake failed (%s)",
tls_error(tls_cctx));
} while(i == TLS_WANT_POLLIN || i == TLS_WANT_POLLOUT);
}
if (tls_cctx) {
int gotcert = tls_peer_cert_provided(tls_cctx);
if (vflag && gotcert)
report_tls(tls_cctx, host, tls_expectname);
if ((TLSopt & TLS_CCERT) && !gotcert)
warnx("No client certificate provided");
else if (gotcert && tls_peer_cert_hash(tls_ctx) && tls_expecthash &&
strcmp(tls_expecthash, tls_peer_cert_hash(tls_ctx)) != 0)
warnx("peer certificate is not %s", tls_expecthash);
else if (gotcert && tls_expectname &&
(!tls_peer_cert_contains_name(tls_cctx, tls_expectname)))
warnx("name (%s) not found in client cert",
tls_expectname);
else {
return tls_cctx;
}
}
return NULL;
}
#endif
int
unix_connect(char *path)
{
struct sockaddr_un s_un;
int s, save_errno;
if (uflag) {
if ((s = unix_bind(unix_dg_tmp_socket, SOCK_CLOEXEC)) < 0)
return (-1);
} else {
if ((s = socket(AF_UNIX, SOCK_STREAM | SOCK_CLOEXEC, 0)) < 0)
return (-1);
}
memset(&s_un, 0, sizeof(struct sockaddr_un));
s_un.sun_family = AF_UNIX;
if (strlcpy(s_un.sun_path, path, sizeof(s_un.sun_path)) >=
sizeof(s_un.sun_path)) {
close(s);
errno = ENAMETOOLONG;
return (-1);
}
if (connect(s, (struct sockaddr *)&s_un, sizeof(s_un)) < 0) {
save_errno = errno;
close(s);
errno = save_errno;
return (-1);
}
return (s);
}
int
unix_listen(char *path)
{
int s;
if ((s = unix_bind(path, 0)) < 0)
return (-1);
if (listen(s, 5) < 0) {
close(s);
return (-1);
}
return (s);
}
int
remote_connect(const char *host, const char *port, struct addrinfo hints)
{
struct addrinfo *res, *res0;
int s = -1, error, save_errno;
#ifdef SO_BINDANY
int on = 1;
#endif
if ((error = getaddrinfo(host, port, &hints, &res0)))
errx(1, "getaddrinfo: %s", gai_strerror(error));
for (res = res0; res; res = res->ai_next) {
if ((s = socket(res->ai_family, res->ai_socktype |
SOCK_NONBLOCK, res->ai_protocol)) < 0)
continue;
if (sflag || pflag) {
struct addrinfo ahints, *ares;
#ifdef SO_BINDANY
setsockopt(s, SOL_SOCKET, SO_BINDANY, &on, sizeof(on));
#endif
memset(&ahints, 0, sizeof(struct addrinfo));
ahints.ai_family = res->ai_family;
ahints.ai_socktype = uflag ? SOCK_DGRAM : SOCK_STREAM;
ahints.ai_protocol = uflag ? IPPROTO_UDP : IPPROTO_TCP;
ahints.ai_flags = AI_PASSIVE;
if ((error = getaddrinfo(sflag, pflag, &ahints, &ares)))
errx(1, "getaddrinfo: %s", gai_strerror(error));
if (bind(s, (struct sockaddr *)ares->ai_addr,
ares->ai_addrlen) < 0)
err(1, "bind failed");
freeaddrinfo(ares);
}
set_common_sockopts(s, res->ai_family);
if (timeout_connect(s, res->ai_addr, res->ai_addrlen) == 0)
break;
if (vflag)
warn("connect to %s port %s (%s) failed", host, port,
uflag ? "udp" : "tcp");
save_errno = errno;
close(s);
errno = save_errno;
s = -1;
}
freeaddrinfo(res0);
return (s);
}
int
timeout_connect(int s, const struct sockaddr *name, socklen_t namelen)
{
struct pollfd pfd;
socklen_t optlen;
int optval;
int ret;
if ((ret = connect(s, name, namelen)) != 0 && errno == EINPROGRESS) {
pfd.fd = s;
pfd.events = POLLOUT;
if ((ret = poll(&pfd, 1, timeout)) == 1) {
optlen = sizeof(optval);
if ((ret = getsockopt(s, SOL_SOCKET, SO_ERROR,
&optval, &optlen)) == 0) {
errno = optval;
ret = optval == 0 ? 0 : -1;
}
} else if (ret == 0) {
errno = ETIMEDOUT;
ret = -1;
} else
err(1, "poll failed");
}
return (ret);
}
int
local_listen(char *host, char *port, struct addrinfo hints)
{
struct addrinfo *res, *res0;
int s = -1, ret, x = 1, save_errno;
int error;
hints.ai_flags |= AI_PASSIVE;
if (host == NULL && hints.ai_family == AF_UNSPEC)
hints.ai_family = AF_INET;
if ((error = getaddrinfo(host, port, &hints, &res0)))
errx(1, "getaddrinfo: %s", gai_strerror(error));
for (res = res0; res; res = res->ai_next) {
if ((s = socket(res->ai_family, res->ai_socktype,
res->ai_protocol)) < 0)
continue;
ret = setsockopt(s, SOL_SOCKET, SO_REUSEPORT, &x, sizeof(x));
if (ret == -1)
err(1, NULL);
set_common_sockopts(s, res->ai_family);
if (bind(s, (struct sockaddr *)res->ai_addr,
res->ai_addrlen) == 0)
break;
save_errno = errno;
close(s);
errno = save_errno;
s = -1;
}
if (!uflag && s != -1) {
if (listen(s, 1) < 0)
err(1, "listen");
}
freeaddrinfo(res0);
return (s);
}
void
readwrite(int net_fd, struct tls *tls_ctx)
{
struct pollfd pfd[4];
int stdin_fd = STDIN_FILENO;
int stdout_fd = STDOUT_FILENO;
unsigned char netinbuf[BUFSIZE];
size_t netinbufpos = 0;
unsigned char stdinbuf[BUFSIZE];
size_t stdinbufpos = 0;
int n, num_fds, done = 0;
ssize_t ret;
if (dflag)
stdin_fd = -1;
pfd[POLL_STDIN].fd = stdin_fd;
pfd[POLL_STDIN].events = POLLIN;
pfd[POLL_NETOUT].fd = net_fd;
pfd[POLL_NETOUT].events = 0;
pfd[POLL_NETIN].fd = net_fd;
pfd[POLL_NETIN].events = POLLIN;
pfd[POLL_STDOUT].fd = stdout_fd;
pfd[POLL_STDOUT].events = 0;
while (!done || pfd[POLL_STDOUT].events == POLLOUT) {
if (pfd[POLL_STDIN].fd == -1 && pfd[POLL_NETIN].fd == -1 &&
stdinbufpos == 0 && netinbufpos == 0) {
close(net_fd);
return;
}
if (pfd[POLL_NETOUT].fd == -1 && pfd[POLL_STDOUT].fd == -1) {
close(net_fd);
return;
}
if (lflag && pfd[POLL_NETIN].fd == -1 &&
stdinbufpos == 0 && netinbufpos == 0) {
close(net_fd);
return;
}
if (iflag)
sleep(iflag);
num_fds = poll(pfd, 4, timeout);
if (num_fds == -1) {
close(net_fd);
err(1, "polling error");
}
if (num_fds == 0)
return;
for (n = 0; n < 4; n++) {
if (pfd[n].revents & (POLLERR|POLLNVAL)) {
pfd[n].fd = -1;
}
}
if (pfd[POLL_STDIN].events & POLLIN &&
pfd[POLL_STDIN].revents & POLLHUP &&
!(pfd[POLL_STDIN].revents & POLLIN))
pfd[POLL_STDIN].fd = -1;
if (pfd[POLL_NETIN].events & POLLIN &&
pfd[POLL_NETIN].revents & POLLHUP &&
!(pfd[POLL_NETIN].revents & POLLIN))
pfd[POLL_NETIN].fd = -1;
if (pfd[POLL_NETOUT].revents & POLLHUP) {
if (Nflag)
shutdown(pfd[POLL_NETOUT].fd, SHUT_WR);
pfd[POLL_NETOUT].fd = -1;
}
if (pfd[POLL_STDOUT].revents & POLLHUP)
pfd[POLL_STDOUT].fd = -1;
if (pfd[POLL_NETOUT].fd == -1)
pfd[POLL_STDIN].fd = -1;
if (pfd[POLL_STDOUT].fd == -1) {
if (pfd[POLL_NETIN].fd != -1)
shutdown(pfd[POLL_NETIN].fd, SHUT_RD);
pfd[POLL_NETIN].fd = -1;
}
if (!done && pfd[POLL_STDIN].revents & POLLIN &&
stdinbufpos < BUFSIZE) {
ret = fillbuf(pfd[POLL_STDIN].fd, stdinbuf,
&stdinbufpos, NULL);
if (ret == TLS_WANT_POLLIN)
pfd[POLL_STDIN].events = POLLIN;
else if (ret == TLS_WANT_POLLOUT)
pfd[POLL_STDIN].events = POLLOUT;
else if (ret == 0 || ret == -1)
pfd[POLL_STDIN].fd = -1;
if (stdinbufpos > 0)
pfd[POLL_NETOUT].events = POLLOUT;
if (stdinbufpos == BUFSIZE)
pfd[POLL_STDIN].events = 0;
}
if (!done && pfd[POLL_NETOUT].revents & POLLOUT &&
stdinbufpos > 0) {
ret = drainbuf(pfd[POLL_NETOUT].fd, stdinbuf,
&stdinbufpos, tls_ctx);
if (ret == TLS_WANT_POLLIN)
pfd[POLL_NETOUT].events = POLLIN;
else if (ret == TLS_WANT_POLLOUT)
pfd[POLL_NETOUT].events = POLLOUT;
else if (ret == -1)
pfd[POLL_NETOUT].fd = -1;
if (stdinbufpos == 0)
pfd[POLL_NETOUT].events = 0;
if (stdinbufpos < BUFSIZE)
pfd[POLL_STDIN].events = POLLIN;
if (maxsend != 0 && --maxsend == 0)
done = 1;
}
if (!done && pfd[POLL_NETIN].revents & POLLIN &&
netinbufpos < BUFSIZE) {
ret = fillbuf(pfd[POLL_NETIN].fd, netinbuf,
&netinbufpos, tls_ctx);
if (ret == TLS_WANT_POLLIN)
pfd[POLL_NETIN].events = POLLIN;
else if (ret == TLS_WANT_POLLOUT)
pfd[POLL_NETIN].events = POLLOUT;
else if (ret == -1)
pfd[POLL_NETIN].fd = -1;
if (ret == 0) {
shutdown(pfd[POLL_NETIN].fd, SHUT_RD);
pfd[POLL_NETIN].fd = -1;
}
if (netinbufpos > 0)
pfd[POLL_STDOUT].events = POLLOUT;
if (netinbufpos == BUFSIZE)
pfd[POLL_NETIN].events = 0;
if (tflag)
atelnet(pfd[POLL_NETIN].fd, netinbuf,
netinbufpos);
if (maxrecv != 0 && --maxrecv == 0)
done = 1;
}
if (pfd[POLL_STDOUT].revents & POLLOUT && netinbufpos > 0) {
ret = drainbuf(pfd[POLL_STDOUT].fd, netinbuf,
&netinbufpos, NULL);
if (ret == TLS_WANT_POLLIN)
pfd[POLL_STDOUT].events = POLLIN;
else if (ret == TLS_WANT_POLLOUT)
pfd[POLL_STDOUT].events = POLLOUT;
else if (ret == -1)
pfd[POLL_STDOUT].fd = -1;
if (netinbufpos == 0)
pfd[POLL_STDOUT].events = 0;
if (netinbufpos < BUFSIZE)
pfd[POLL_NETIN].events = POLLIN;
}
if (pfd[POLL_STDIN].fd == -1 && stdinbufpos == 0) {
if (pfd[POLL_NETOUT].fd != -1 && Nflag)
shutdown(pfd[POLL_NETOUT].fd, SHUT_WR);
pfd[POLL_NETOUT].fd = -1;
}
if (pfd[POLL_NETIN].fd == -1 && netinbufpos == 0) {
pfd[POLL_STDOUT].fd = -1;
}
}
if (pfd[POLL_NETOUT].fd != -1 && Nflag)
shutdown(pfd[POLL_NETOUT].fd, SHUT_WR);
close(net_fd);
}
ssize_t
drainbuf(int fd, unsigned char *buf, size_t *bufpos, struct tls *tls)
{
ssize_t n;
ssize_t adjust;
#ifdef CRYPTO
if (tls)
n = tls_write(tls, buf, *bufpos);
else
#endif
{
n = write(fd, buf, *bufpos);
if (n == -1 && (errno == EAGAIN || errno == EINTR))
n = TLS_WANT_POLLOUT;
}
if (n <= 0)
return n;
adjust = *bufpos - n;
if (adjust > 0)
memmove(buf, buf + n, adjust);
*bufpos -= n;
return n;
}
ssize_t
fillbuf(int fd, unsigned char *buf, size_t *bufpos, struct tls *tls)
{
size_t num = BUFSIZE - *bufpos;
ssize_t n;
#ifdef CRYPTO
if (tls)
n = tls_read(tls, buf + *bufpos, num);
else
#endif
{
n = read(fd, buf + *bufpos, num);
if (n == -1 && (errno == EAGAIN || errno == EINTR))
n = TLS_WANT_POLLIN;
}
if (n <= 0)
return n;
*bufpos += n;
return n;
}
void
fdpass(int nfd)
{
struct msghdr mh;
union {
struct cmsghdr hdr;
char buf[CMSG_SPACE(sizeof(int))];
} cmsgbuf;
struct cmsghdr *cmsg;
struct iovec iov;
char c = '\0';
ssize_t r;
struct pollfd pfd;
if (isatty(STDOUT_FILENO))
errx(1, "Cannot pass file descriptor to tty");
bzero(&mh, sizeof(mh));
bzero(&cmsgbuf, sizeof(cmsgbuf));
bzero(&iov, sizeof(iov));
mh.msg_control = (caddr_t)&cmsgbuf.buf;
mh.msg_controllen = sizeof(cmsgbuf.buf);
cmsg = CMSG_FIRSTHDR(&mh);
cmsg->cmsg_len = CMSG_LEN(sizeof(int));
cmsg->cmsg_level = SOL_SOCKET;
cmsg->cmsg_type = SCM_RIGHTS;
*(int *)CMSG_DATA(cmsg) = nfd;
iov.iov_base = &c;
iov.iov_len = 1;
mh.msg_iov = &iov;
mh.msg_iovlen = 1;
bzero(&pfd, sizeof(pfd));
pfd.fd = STDOUT_FILENO;
pfd.events = POLLOUT;
for (;;) {
r = sendmsg(STDOUT_FILENO, &mh, 0);
if (r == -1) {
if (errno == EAGAIN || errno == EINTR) {
if (poll(&pfd, 1, -1) == -1)
err(1, "poll");
continue;
}
err(1, "sendmsg");
} else if (r != 1)
errx(1, "sendmsg: unexpected return value %zd", r);
else
break;
}
exit(0);
}
void
atelnet(int nfd, unsigned char *buf, unsigned int size)
{
unsigned char *p, *end;
unsigned char obuf[4];
if (size < 3)
return;
end = buf + size - 2;
for (p = buf; p < end; p++) {
if (*p != IAC)
continue;
obuf[0] = IAC;
p++;
if ((*p == WILL) || (*p == WONT))
obuf[1] = DONT;
else if ((*p == DO) || (*p == DONT))
obuf[1] = WONT;
else
continue;
p++;
obuf[2] = *p;
if (atomicio(vwrite, nfd, obuf, 3) != 3)
warn("Write Error!");
}
}
static int
strtoport(const char *portstr, int udp)
{
struct servent *entry;
int errnum;
const char *proto;
int port;
proto = udp ? "udp" : "tcp";
port = strtoi(portstr, NULL, 0, 1, PORT_MAX, &errnum);
if (errnum == 0)
return port;
if ((entry = getservbyname(portstr, proto)) == NULL)
errx(1, "service \"%s\" unknown", portstr);
return ntohs(entry->s_port);
}
void
build_ports(char *p)
{
char *n;
int hi, lo, cp;
int x = 0;
if ((n = strchr(p, '-')) != NULL) {
*n = '\0';
n++;
hi = strtoport(n, uflag);
lo = strtoport(p, uflag);
if (lo > hi) {
cp = hi;
hi = lo;
lo = cp;
}
if (rflag) {
for (x = 0; x <= hi - lo; x++) {
cp = arc4random_uniform(x + 1);
portlist[x] = portlist[cp];
if (asprintf(&portlist[cp], "%d", x + lo) < 0)
err(1, "asprintf");
}
} else {
for (cp = lo; cp <= hi; cp++) {
if (asprintf(&portlist[x], "%d", cp) < 0)
err(1, "asprintf");
x++;
}
}
} else {
char *tmp;
hi = strtoport(p, uflag);
if (asprintf(&tmp, "%d", hi) != -1)
portlist[0] = tmp;
else
err(1, NULL);
}
}
int
udptest(int s)
{
int i, ret;
for (i = 0; i <= 3; i++) {
if (write(s, "X", 1) == 1)
ret = 1;
else
ret = -1;
}
return (ret);
}
void
set_common_sockopts(int s, int af)
{
int x = 1;
if (Sflag) {
if (setsockopt(s, IPPROTO_TCP, TCP_MD5SIG,
&x, sizeof(x)) == -1)
err(1, NULL);
}
if (Dflag) {
if (setsockopt(s, SOL_SOCKET, SO_DEBUG,
&x, sizeof(x)) == -1)
err(1, NULL);
}
if (Tflag != -1) {
if (af == AF_INET && setsockopt(s, IPPROTO_IP,
IP_TOS, &Tflag, sizeof(Tflag)) == -1)
err(1, "set IP ToS");
else if (af == AF_INET6 && setsockopt(s, IPPROTO_IPV6,
IPV6_TCLASS, &Tflag, sizeof(Tflag)) == -1)
err(1, "set IPv6 traffic class");
}
if (Iflag) {
if (setsockopt(s, SOL_SOCKET, SO_RCVBUF,
&Iflag, sizeof(Iflag)) == -1)
err(1, "set TCP receive buffer size");
}
if (Oflag) {
if (setsockopt(s, SOL_SOCKET, SO_SNDBUF,
&Oflag, sizeof(Oflag)) == -1)
err(1, "set TCP send buffer size");
}
if (ttl != -1) {
if (af == AF_INET && setsockopt(s, IPPROTO_IP,
IP_TTL, &ttl, sizeof(ttl)))
err(1, "set IP TTL");
else if (af == AF_INET6 && setsockopt(s, IPPROTO_IPV6,
IPV6_UNICAST_HOPS, &ttl, sizeof(ttl)))
err(1, "set IPv6 unicast hops");
}
if (minttl != -1) {
if (af == AF_INET && setsockopt(s, IPPROTO_IP,
IP_MINTTL, &minttl, sizeof(minttl)))
err(1, "set IP min TTL");
#ifdef IPV6_MINHOPCOUNT
else if (af == AF_INET6 && setsockopt(s, IPPROTO_IPV6,
IPV6_MINHOPCOUNT, &minttl, sizeof(minttl)))
err(1, "set IPv6 min hop count");
#endif
}
}
int
map_tos(char *s, int *val)
{
const struct toskeywords {
const char *keyword;
int val;
} *t, toskeywords[] = {
{ "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 },
{ "critical", IPTOS_PREC_CRITIC_ECP },
{ "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 },
{ "inetcontrol", IPTOS_PREC_INTERNETCONTROL },
{ "lowdelay", IPTOS_LOWDELAY },
{ "netcontrol", IPTOS_PREC_NETCONTROL },
{ "reliability", IPTOS_RELIABILITY },
{ "throughput", IPTOS_THROUGHPUT },
{ NULL, -1 },
};
for (t = toskeywords; t->keyword != NULL; t++) {
if (strcmp(s, t->keyword) == 0) {
*val = t->val;
return (1);
}
}
return (0);
}
#ifdef CRYPTO
int
map_tls(char *s, int *val)
{
const struct tlskeywords {
const char *keyword;
int val;
} *t, tlskeywords[] = {
{ "tlsall", TLS_ALL },
{ "noverify", TLS_NOVERIFY },
{ "noname", TLS_NONAME },
{ "clientcert", TLS_CCERT},
{ "muststaple", TLS_MUSTSTAPLE},
{ NULL, -1 },
};
for (t = tlskeywords; t->keyword != NULL; t++) {
if (strcmp(s, t->keyword) == 0) {
*val |= t->val;
return (1);
}
}
return (0);
}
void
report_tls(struct tls * tls_ctx, char * host, char *tlsexpectname)
{
time_t t;
const char *ocsp_url;
fprintf(stderr, "TLS handshake negotiated %s/%s with host %s\n",
tls_conn_version(tls_ctx), tls_conn_cipher(tls_ctx), host);
fprintf(stderr, "Peer name: %s\n",
tlsexpectname ? tlsexpectname : host);
if (tls_peer_cert_subject(tls_ctx))
fprintf(stderr, "Subject: %s\n",
tls_peer_cert_subject(tls_ctx));
if (tls_peer_cert_issuer(tls_ctx))
fprintf(stderr, "Issuer: %s\n",
tls_peer_cert_issuer(tls_ctx));
if ((t = tls_peer_cert_notbefore(tls_ctx)) != -1)
fprintf(stderr, "Valid From: %s", ctime(&t));
if ((t = tls_peer_cert_notafter(tls_ctx)) != -1)
fprintf(stderr, "Valid Until: %s", ctime(&t));
if (tls_peer_cert_hash(tls_ctx))
fprintf(stderr, "Cert Hash: %s\n",
tls_peer_cert_hash(tls_ctx));
ocsp_url = tls_peer_ocsp_url(tls_ctx);
if (ocsp_url != NULL)
fprintf(stderr, "OCSP URL: %s\n", ocsp_url);
switch (tls_peer_ocsp_response_status(tls_ctx)) {
case TLS_OCSP_RESPONSE_SUCCESSFUL:
fprintf(stderr, "OCSP Stapling: %s\n",
tls_peer_ocsp_result(tls_ctx) == NULL ? "" :
tls_peer_ocsp_result(tls_ctx));
fprintf(stderr,
" response_status=%d cert_status=%d crl_reason=%d\n",
tls_peer_ocsp_response_status(tls_ctx),
tls_peer_ocsp_cert_status(tls_ctx),
tls_peer_ocsp_crl_reason(tls_ctx));
t = tls_peer_ocsp_this_update(tls_ctx);
fprintf(stderr, " this update: %s",
t != -1 ? ctime(&t) : "\n");
t = tls_peer_ocsp_next_update(tls_ctx);
fprintf(stderr, " next update: %s",
t != -1 ? ctime(&t) : "\n");
t = tls_peer_ocsp_revocation_time(tls_ctx);
fprintf(stderr, " revocation: %s",
t != -1 ? ctime(&t) : "\n");
break;
case -1:
break;
default:
fprintf(stderr, "OCSP Stapling: failure - response_status %d (%s)\n",
tls_peer_ocsp_response_status(tls_ctx),
tls_peer_ocsp_result(tls_ctx) == NULL ? "" :
tls_peer_ocsp_result(tls_ctx));
break;
}
}
#endif
void
report_connect(const struct sockaddr *sa, socklen_t salen, char *path)
{
char remote_host[NI_MAXHOST];
char remote_port[NI_MAXSERV];
int herr;
int flags = NI_NUMERICSERV;
if (path != NULL) {
fprintf(stderr, "Connection on %s received!\n", path);
return;
}
if (nflag)
flags |= NI_NUMERICHOST;
if ((herr = getnameinfo(sa, salen,
remote_host, sizeof(remote_host),
remote_port, sizeof(remote_port),
flags)) != 0) {
if (herr == EAI_SYSTEM)
err(1, "getnameinfo");
else
errx(1, "getnameinfo: %s", gai_strerror(herr));
}
fprintf(stderr,
"Connection from %s %s "
"received!\n", remote_host, remote_port);
}
void
help(void)
{
usage(0);
fprintf(stderr, "\tCommand Summary:\n"
"\t-4 Use IPv4\n"
"\t-6 Use IPv6\n"
#ifdef CRYPTO
"\t-C certfile Public key file\n"
"\t-c Use TLS\n"
#endif
"\t-D Enable the debug socket option\n"
"\t-d Detach from stdin\n"
"\t-E [s]/[r] Exit after sending s or receiving r (pkts)\n"
"\t-E n (same as -E n/n)\n"
#ifdef CRYPTO
"\t-e name\t Required name in peer certificate\n"
#endif
"\t-F Pass socket fd\n"
#ifdef CRYPTO
"\t-H hash\t Hash string of peer certificate\n"
#endif
"\t-h This help text\n"
"\t-I length TCP receive buffer length\n"
"\t-i interval Delay interval for lines sent, ports scanned\n"
#ifdef CRYPTO
"\t-K keyfile Private key file\n"
#endif
"\t-k Keep inbound sockets open for multiple connects\n"
"\t-l Listen mode, for inbound connects\n"
"\t-M ttl Outgoing TTL / Hop Limit\n"
"\t-m minttl Minimum incoming TTL / Hop Limit\n"
"\t-N Shutdown the network socket after EOF on stdin\n"
"\t-n Suppress name/port resolutions\n"
"\t-O length TCP send buffer length\n"
#ifdef CRYPTO
"\t-o staplefile Staple file\n"
#endif
"\t-P proxyuser\tUsername for proxy authentication\n"
"\t-p port\t Specify local port for remote connects\n"
#ifdef CRYPTO
"\t-R CAfile CA bundle\n"
#endif
"\t-r Randomize remote ports\n"
"\t-S Enable the TCP MD5 signature option\n"
"\t-s source Local source address\n"
#ifdef CRYPTO
"\t-T keyword TOS value or TLS options\n"
#endif
"\t-t Answer TELNET negotiation\n"
"\t-U Use UNIX domain socket\n"
"\t-u UDP mode\n"
#ifdef __OpenBSD__
"\t-V rtable Specify alternate routing table\n"
#endif
"\t-v Verbose\n"
"\t-w timeout Timeout for connects and final net reads\n"
"\t-X proto Proxy protocol: \"4\", \"5\" (SOCKS) or \"connect\"\n"
"\t-x addr[:port]\tSpecify proxy address and port\n"
"\t-z Zero-I/O mode [used for scanning]\n"
"Port numbers can be individual or ranges: lo-hi [inclusive]\n");
exit(1);
}
void
usage(int ret)
{
fprintf(stderr,
"Usage: %s [-46%sDdFhklNnrStUuvz] [-E [s]/[r] | -E n] "
"[-I length]\n"
#ifdef CRYPTO
"\t [-C certfile] [-e name] [-H hash] "
"[-K keyfile] [-R CAfile] [-T keyword] [-o staplefile]\n"
#endif
"\t [-i interval] [-M ttl] [-m minttl] [-O length]\n"
"\t [-P proxy_username] [-p source_port]\n"
"\t [-s source] "
#ifdef __OpenBSD__
"[-V rtable] "
#endif
"[-w timeout] [-X proxy_protocol]\n"
"\t [-x proxy_address[:port]] [destination] [port]\n",
getprogname(),
#ifdef CRYPTO
"c"
#else
""
#endif
);
if (ret)
exit(1);
}
