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tunnel.c
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tunnel.c
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/*
tunnel.c
Copyright (C) 1999, 2000 Lars Brinkhoff. See COPYING for terms and conditions.
See tunnel.h for some documentation about the programming interface.
*/
#include <time.h>
#include <stdio.h>
#include <netdb_.h>
#include <fcntl.h>
#include <stdlib.h>
#include <sys/poll_.h>
#include <sys/types.h>
#include <sys/socket.h>
#include <netinet/tcp.h>
#include "http.h"
#include "tunnel.h"
#include "common.h"
/* #define IO_COUNT_HTTP_HEADER */
/* #define USE_SHUTDOWN */
#define READ_TRAIL_TIMEOUT (1 * 1000) /* milliseconds */
#define ACCEPT_TIMEOUT 10 /* seconds */
#define min(a, b) ((a) < (b) ? (a) : (b))
#define TUNNEL_IN 1
#define TUNNEL_OUT 2
#if SIZEOF_CHAR == 1
typedef unsigned char Request;
#else
#error "FIXME: Can't handle SIZEOF_CHAR != 1"
#endif
#if SIZEOF_SHORT == 2
typedef unsigned short Length;
#else
#error "FIXME: Can't handle SIZEOF_SHORT != 2"
#endif
enum tunnel_request
{
TUNNEL_SIMPLE = 0x40,
TUNNEL_OPEN = 0x01,
TUNNEL_DATA = 0x02,
TUNNEL_PADDING = 0x03,
TUNNEL_ERROR = 0x04,
TUNNEL_PAD1 = TUNNEL_SIMPLE | 0x05,
TUNNEL_CLOSE = TUNNEL_SIMPLE | 0x06,
TUNNEL_DISCONNECT = TUNNEL_SIMPLE | 0x07
};
static inline const char *
REQ_TO_STRING (Request request)
{
switch (request)
{
case TUNNEL_OPEN: return "TUNNEL_OPEN";
case TUNNEL_DATA: return "TUNNEL_DATA";
case TUNNEL_PADDING: return "TUNNEL_PADDING";
case TUNNEL_ERROR: return "TUNNEL_ERROR";
case TUNNEL_PAD1: return "TUNNEL_PAD1";
case TUNNEL_CLOSE: return "TUNNEL_CLOSE";
case TUNNEL_DISCONNECT: return "TUNNEL_DISCONNECT";
default: return "(unknown)";
}
}
struct tunnel
{
int in_fd, out_fd;
int server_socket;
Http_destination dest;
struct sockaddr_in address;
size_t bytes;
size_t content_length;
char buf[65536];
char *buf_ptr;
size_t buf_len;
int padding_only;
size_t in_total_raw;
size_t in_total_data;
size_t out_total_raw;
size_t out_total_data;
time_t out_connect_time;
int strict_content_length;
int keep_alive;
int max_connection_age;
};
static const size_t sizeof_header = sizeof (Request) + sizeof (Length);
static inline int
tunnel_is_disconnected (Tunnel *tunnel)
{
return tunnel->out_fd == -1;
}
static inline int
tunnel_is_connected (Tunnel *tunnel)
{
return !tunnel_is_disconnected (tunnel);
}
static inline int
tunnel_is_server (Tunnel *tunnel)
{
return tunnel->server_socket != -1;
}
static inline int
tunnel_is_client (Tunnel *tunnel)
{
return !tunnel_is_server (tunnel);
}
#if 1
static int
get_proto_number (const char *name)
{
struct protoent *p;
int number;
p = getprotobyname (name);
if (p == NULL)
number = -1;
else
number = p->p_proto;
endprotoent ();
return number;
}
#endif
static int
tunnel_in_setsockopts (int fd)
{
#ifdef SO_RCVLOWAT
int i, n;
i = 1;
if (setsockopt (fd,
SOL_SOCKET,
SO_RCVLOWAT,
(void *)&i,
sizeof i) == -1)
{
log_debug ("tunnel_in_setsockopts: non-fatal SO_RCVLOWAT error: %s",
strerror (errno));
}
n = sizeof i;
getsockopt (fd,
SOL_SOCKET,
SO_RCVLOWAT,
(void *)&i,
&n);
log_debug ("tunnel_out_setsockopts: SO_RCVLOWAT: %d", i);
#endif /* SO_RCVLOWAT */
return 0;
}
static int
tunnel_out_setsockopts (int fd)
{
#ifdef SO_SNDLOWAT
{
int i, n;
i = 1;
if (setsockopt (fd,
SOL_SOCKET,
SO_SNDLOWAT,
(void *)&i,
sizeof i) == -1)
{
log_debug ("tunnel_out_setsockopts: "
"non-fatal SO_SNDLOWAT error: %s",
strerror (errno));
}
n = sizeof i;
getsockopt (fd,
SOL_SOCKET,
SO_SNDLOWAT,
(void *)&i,
&n);
log_debug ("tunnel_out_setsockopts: non-fatal SO_SNDLOWAT: %d", i);
}
#endif /* SO_SNDLOWAT */
#ifdef SO_LINGER
{
struct linger l;
int n;
l.l_onoff = 1;
l.l_linger = 20 * 100; /* linger for 20 seconds */
if (setsockopt (fd,
SOL_SOCKET,
SO_LINGER,
(void *)&l,
sizeof l) == -1)
{
log_debug ("tunnel_out_setsockopts: non-fatal SO_LINGER error: %s",
strerror (errno));
}
n = sizeof l;
getsockopt (fd,
SOL_SOCKET,
SO_LINGER,
(void *)&l,
&n);
log_debug ("tunnel_out_setsockopts: SO_LINGER: onoff=%d linger=%d",
l.l_onoff, l.l_linger);
}
#endif /* SO_LINGER */
#ifdef TCP_NODELAY
{
int tcp = get_proto_number ("tcp");
int i, n;
if (tcp != -1)
{
i = 1;
if (setsockopt (fd,
tcp,
TCP_NODELAY,
(void *)&i,
sizeof i) == -1)
{
log_debug ("tunnel_out_setsockopts: "
"non-fatal TCP_NODELAY error: %s",
strerror (errno));
}
n = sizeof i;
getsockopt (fd,
tcp,
TCP_NODELAY,
(void *)&i,
&n);
log_debug ("tunnel_out_setsockopts: non-fatal TCP_NODELAY: %d", i);
}
}
#else
#ifdef SO_SNDBUF
{
int i, n;
i = 0;
if (setsockopt (fd,
SOL_SOCKET,
SO_SNDBUF,
(void *)&i,
sizeof i) == -1)
{
log_debug ("tunnel_out_setsockopts: non-fatal SO_SNDBUF error: %s",
strerror (errno));
}
n = sizeof i;
getsockopt (fd,
SOL_SOCKET,
SO_SNDBUF,
(void *)&i,
&n);
log_debug ("tunnel_out_setsockopts: SO_SNDBUF: %d", i);
}
#endif /* SO_SNDBUF */
#endif /* TCP_NODELAY */
#ifdef SO_KEEPALIVE
{
int i, n;
i = 1;
if (setsockopt (fd,
SOL_SOCKET,
SO_KEEPALIVE,
(void *)&i,
sizeof i) == -1)
{
log_debug ("tunnel_out_setsockopts: non-fatal SO_KEEPALIVE error: %s",
strerror (errno));
}
n = sizeof i;
getsockopt (fd,
SOL_SOCKET,
SO_KEEPALIVE,
(void *)&i,
&n);
log_debug ("tunnel_out_setsockopts: SO_KEEPALIVE: %d", i);
}
#endif /* SO_KEEPALIVE */
return 0;
}
static void
tunnel_out_disconnect (Tunnel *tunnel)
{
if (tunnel_is_disconnected (tunnel))
return;
#ifdef DEBUG_MODE
if (tunnel_is_client (tunnel) &&
tunnel->bytes != tunnel->content_length + 1)
log_error ("tunnel_out_disconnect: warning: "
"bytes=%d != content_length=%d",
tunnel->bytes, tunnel->content_length + 1);
#endif
close (tunnel->out_fd);
tunnel->out_fd = -1;
tunnel->bytes = 0;
tunnel->buf_ptr = tunnel->buf;
tunnel->buf_len = 0;
log_debug ("tunnel_out_disconnect: output disconnected");
}
static void
tunnel_in_disconnect (Tunnel *tunnel)
{
if (tunnel->in_fd == -1)
return;
close (tunnel->in_fd);
tunnel->in_fd = -1;
log_debug ("tunnel_in_disconnect: input disconnected");
}
static int
tunnel_out_connect (Tunnel *tunnel)
{
ssize_t n;
if (tunnel_is_connected (tunnel))
{
log_debug ("tunnel_out_connect: already connected");
tunnel_out_disconnect (tunnel);
}
tunnel->out_fd = do_connect (&tunnel->address);
if (tunnel->out_fd == -1)
{
log_error ("tunnel_out_connect: do_connect (%d.%d.%d.%d:%u) error: %s",
ntohl (tunnel->address.sin_addr.s_addr) >> 24,
(ntohl (tunnel->address.sin_addr.s_addr) >> 16) & 0xff,
(ntohl (tunnel->address.sin_addr.s_addr) >> 8) & 0xff,
ntohl (tunnel->address.sin_addr.s_addr) & 0xff,
ntohs (tunnel->address.sin_port),
strerror (errno));
return -1;
}
tunnel_out_setsockopts (tunnel->out_fd);
#ifdef USE_SHUTDOWN
shutdown (tunnel->out_fd, 0);
#endif
/* + 1 to allow for TUNNEL_DISCONNECT */
n = http_post (tunnel->out_fd,
&tunnel->dest,
tunnel->content_length + 1);
if (n == -1)
return -1;
#ifdef IO_COUNT_HTTP_HEADER
tunnel->out_total_raw += n;
log_annoying ("tunnel_out_connect: out_total_raw = %u",
tunnel->out_total_raw);
#endif
tunnel->bytes = 0;
tunnel->buf_ptr = tunnel->buf;
tunnel->buf_len = 0;
tunnel->padding_only = TRUE;
time (&tunnel->out_connect_time);
log_debug ("tunnel_out_connect: output connected");
return 0;
}
static int
tunnel_in_connect (Tunnel *tunnel)
{
Http_response *response;
ssize_t n;
log_verbose ("tunnel_in_connect()");
if (tunnel->in_fd != -1)
{
log_error ("tunnel_in_connect: already connected");
return -1;
}
tunnel->in_fd = do_connect (&tunnel->address);
if (tunnel->in_fd == -1)
{
log_error ("tunnel_in_connect: do_connect() error: %s",
strerror (errno));
return -1;
}
tunnel_in_setsockopts (tunnel->in_fd);
if (http_get (tunnel->in_fd, &tunnel->dest) == -1)
return -1;
#ifdef USE_SHUTDOWN
if (shutdown (tunnel->in_fd, 1) == -1)
{
log_error ("tunnel_in_connect: shutdown() error: %s",
strerror (errno));
return -1;
}
#endif
n = http_parse_response (tunnel->in_fd, &response);
if (n <= 0)
{
if (n == 0)
log_error ("tunnel_in_connect: no response; peer "
"closed connection");
else
log_error ("tunnel_in_connect: no response; error: %s",
strerror (errno));
}
else if (response->major_version != 1 ||
(response->minor_version != 1 &&
response->minor_version != 0))
{
log_error ("tunnel_in_connect: unknown HTTP version: %d.%d",
response->major_version, response->minor_version);
n = -1;
}
else if (response->status_code != 200)
{
log_error ("tunnel_in_connect: HTTP error %d", response->status_code);
errno = http_error_to_errno (-response->status_code);
n = -1;
}
if (response)
http_destroy_response (response);
if (n > 0)
{
#ifdef IO_COUNT_HTTP_HEADER
tunnel->in_total_raw += n;
log_annoying ("tunnel_in_connect: in_total_raw = %u",
tunnel->in_total_raw);
#endif
}
else
{
return n;
}
log_debug ("tunnel_in_connect: input connected");
return 1;
}
static inline ssize_t
tunnel_write_data (Tunnel *tunnel, void *data, size_t length)
{
if (write_all (tunnel->out_fd, data, length) == -1)
{
log_error ("tunnel_write_data: write error: %s", strerror (errno));
return -1;
}
tunnel->bytes += length;
return length;
}
static int
tunnel_write_request (Tunnel *tunnel, Request request,
void *data, Length length)
{
if (tunnel->bytes + sizeof request +
(data ? sizeof length + length : 0) > tunnel->content_length)
tunnel_padding (tunnel, tunnel->content_length - tunnel->bytes);
#if 1 /* FIXME: this is a kludge */
{
time_t t;
time (&t);
if (tunnel_is_client (tunnel) &&
tunnel_is_connected (tunnel) &&
t - tunnel->out_connect_time > tunnel->max_connection_age)
{
char c = TUNNEL_DISCONNECT;
log_debug ("tunnel_write_request: connection > %d seconds old",
tunnel->max_connection_age);
if (tunnel->strict_content_length)
{
int l = tunnel->content_length - tunnel->bytes - 1;
log_debug ("tunnel_write_request: write padding (%d bytes)",
tunnel->content_length - tunnel->bytes - 1);
if (l > 3)
{
char c;
short s;
int i;
c = TUNNEL_PADDING;
tunnel_write_data (tunnel, &c, sizeof c);
s = htons(l-2);
tunnel_write_data (tunnel, &s, sizeof s);
l -= 2;
c = 0;
for (i=0; i<l; i++)
tunnel_write_data (tunnel, &c, sizeof c);
}
else
{
char c = TUNNEL_PAD1;
int i;
for (i=0; i<l; i++)
tunnel_write_data (tunnel, &c, sizeof c);
}
}
log_debug ("tunnel_write_request: closing old connection");
if (tunnel_write_data (tunnel, &c, sizeof c) <= 0)
return -1;
tunnel_out_disconnect (tunnel);
}
}
#endif
if (tunnel_is_disconnected (tunnel))
{
if (tunnel_is_client (tunnel))
{
if (tunnel_out_connect (tunnel) == -1)
return -1;
}
else
{
#if 0
log_error ("tunnel_write_request: output is disconnected");
errno = EIO;
return -1;
#else
if (tunnel_accept (tunnel) == -1)
return -1;
#endif
}
}
if (request != TUNNEL_PADDING && request != TUNNEL_PAD1)
tunnel->padding_only = FALSE;
if (tunnel_write_data (tunnel, &request, sizeof request) == -1)
{
if (errno != EPIPE)
return -1;
tunnel_out_disconnect (tunnel);
if (tunnel_is_client (tunnel))
tunnel_out_connect (tunnel);
else
{
log_error ("tunnel_write_request: couldn't write request: "
"output is disconnected");
errno = EIO;
return -1;
}
/* return tunnel_write_request (tunnel, request, data, length); */
if (tunnel_write_data (tunnel, &request, sizeof request) == -1)
return -1;
}
if (data)
{
Length network_length = htons ((short)length);
if (tunnel_write_data (tunnel,
&network_length,
sizeof network_length) == -1)
return -1;
#ifdef DEBUG_MODE
if (request == TUNNEL_DATA && debug_level >= 5)
{
log_annoying ("tunnel_write_request: TUNNEL_DATA:");
dump_buf (debug_file, data, (size_t)length);
}
#endif
if (tunnel_write_data (tunnel, data, (size_t)length) == -1)
return -1;
}
if (data)
{
tunnel->out_total_raw += 3 + length;
if (request == TUNNEL_DATA)
log_verbose ("tunnel_write_request: %s (%d)",
REQ_TO_STRING (request), length);
else
log_debug ("tunnel_write_request: %s (%d)",
REQ_TO_STRING (request), length);
}
else
{
tunnel->out_total_raw += 1;
log_debug ("tunnel_write_request: %s", REQ_TO_STRING (request));
}
log_annoying ("tunnel_write_data: out_total_raw = %u",
tunnel->out_total_raw);
#ifdef DEBUG_MODE
if (tunnel->bytes > tunnel->content_length)
log_debug ("tunnel_write_request: tunnel->bytes > tunnel->content_length");
#endif
if (tunnel->bytes >= tunnel->content_length)
{
char c = TUNNEL_DISCONNECT;
tunnel_write_data (tunnel, &c, sizeof c);
tunnel_out_disconnect (tunnel);
#if 0
if (tunnel_is_server (tunnel))
tunnel_accept (tunnel);
#endif
}
return 0;
}
int
tunnel_connect (Tunnel *tunnel)
{
char auth_data[1] = { 42 }; /* dummy data, not used by server */
log_verbose ("tunnel_connect()");
if (tunnel_is_connected (tunnel))
{
log_error ("tunnel_connect: already connected");
errno = EINVAL;
return -1;
}
if (tunnel_write_request (tunnel, TUNNEL_OPEN,
auth_data, sizeof auth_data) == -1)
return -1;
if (tunnel_in_connect (tunnel) <= 0)
return -1;
return 0;
}
static inline int
tunnel_write_or_padding (Tunnel *tunnel, Request request, void *data,
size_t length)
{
static char padding[65536];
size_t n, remaining;
char *wdata = data;
for (remaining = length; remaining > 0; remaining -= n, wdata += n)
{
if (tunnel->bytes + remaining > tunnel->content_length - sizeof_header &&
tunnel->content_length - tunnel->bytes > sizeof_header)
n = tunnel->content_length - sizeof_header - tunnel->bytes;
else if (remaining > tunnel->content_length - sizeof_header)
n = tunnel->content_length - sizeof_header;
else
n = remaining;
if (n > 65535)
n = 65535;
if (request == TUNNEL_PADDING)
{
if (n + sizeof_header > remaining)
n = remaining - sizeof_header;
if (tunnel_write_request (tunnel, request, padding, n) == -1)
break;
n += sizeof_header;
}
else
{
if (tunnel_write_request (tunnel, request, wdata, n) == -1)
break;
}
}
return length - remaining;
}
ssize_t
tunnel_write (Tunnel *tunnel, void *data, size_t length)
{
ssize_t n;
n = tunnel_write_or_padding (tunnel, TUNNEL_DATA, data, length);
tunnel->out_total_data += length;
log_verbose ("tunnel_write: out_total_data = %u", tunnel->out_total_data);
return n;
}
ssize_t
tunnel_padding (Tunnel *tunnel, size_t length)
{
if (length < sizeof_header + 1)
{
int i;
for (i = 0; i < length; i++)
tunnel_write_request (tunnel, TUNNEL_PAD1, NULL, 0);
return length;
}
return tunnel_write_or_padding (tunnel, TUNNEL_PADDING, NULL, length);
}
int
tunnel_close (Tunnel *tunnel)
{
struct pollfd p;
char buf[10240];
ssize_t n;
if (tunnel->strict_content_length)
{
log_debug ("tunnel_close: write padding (%d bytes)",
tunnel->content_length - tunnel->bytes - 1);
tunnel_padding (tunnel, tunnel->content_length - tunnel->bytes - 1);
}
log_debug ("tunnel_close: write TUNNEL_CLOSE request");
tunnel_write_request (tunnel, TUNNEL_CLOSE, NULL, 0);
tunnel_out_disconnect (tunnel);
log_debug ("tunnel_close: reading trailing data from input ...");
p.fd = tunnel->in_fd;
p.events = POLLIN;
while (poll (&p, 1, READ_TRAIL_TIMEOUT) > 0)
{
if (p.revents & POLLIN)
{
n = read (tunnel->in_fd, buf, sizeof buf);
if (n > 0)
{
log_annoying ("read (%d, %p, %d) = %d",
tunnel->in_fd, buf, sizeof buf, n);
continue;
}
else if (n == -1 && errno == EAGAIN)
continue;
else if (n == -1)
log_debug ("tunnel_close: ... error: %s", strerror (errno));
else
log_debug ("tunnel_close: ... done (tunnel closed)");
}
if (p.revents & POLLHUP)
log_debug ("POLLHUP");
if (p.revents & POLLERR)
log_debug ("POLLERR");
if (p.revents & POLLNVAL)
log_debug ("POLLNVAL");
break;
}
tunnel_in_disconnect (tunnel);
tunnel->buf_len = 0;
tunnel->in_total_raw = 0;
tunnel->in_total_data = 0;
tunnel->out_total_raw = 0;
tunnel->out_total_data = 0;
return 0;
}
static int
tunnel_read_request (Tunnel *tunnel, enum tunnel_request *request,
unsigned char *buf, size_t *length)
{
Request req;
Length len;
ssize_t n;
log_annoying ("read (%d, %p, %d) ...", tunnel->in_fd, &req, 1);
n = read (tunnel->in_fd, &req, 1);
log_annoying ("... = %d", n);
if (n == -1)
{
if (errno != EAGAIN)
log_error ("tunnel_read_request: error reading request: %s",
strerror (errno));
return n;
}
else if (n == 0)
{
log_debug ("tunnel_read_request: connection closed by peer");
tunnel_in_disconnect (tunnel);
if (tunnel_is_client (tunnel)
&& tunnel_in_connect (tunnel) == -1)
return -1;
errno = EAGAIN;
return -1;
}
*request = req;
tunnel->in_total_raw += n;
log_annoying ("request = 0x%x (%s)", req, REQ_TO_STRING (req));
if (req & TUNNEL_SIMPLE)
{
log_annoying ("tunnel_read_request: in_total_raw = %u",
tunnel->in_total_raw);
log_debug ("tunnel_read_request: %s", REQ_TO_STRING (req));
*length = 0;
return 1;
}
n = read_all (tunnel->in_fd, &len, 2);
if (n <= 0)
{
log_error ("tunnel_read_request: error reading request length: %s",
strerror (errno));
if (n == 0)
errno = EIO;
return -1;
}
len = ntohs (len);
*length = len;
tunnel->in_total_raw += n;
log_annoying ("length = %d", len);
if (len > 0)
{
n = read_all (tunnel->in_fd, buf, (size_t)len);
if (n <= 0)
{
log_error ("tunnel_read_request: error reading request data: %s",
strerror (errno));
if (n == 0)
errno = EIO;
return -1;
}
tunnel->in_total_raw += n;
log_annoying ("tunnel_read_request: in_total_raw = %u",
tunnel->in_total_raw);
}
if (req == TUNNEL_DATA)
log_verbose ("tunnel_read_request: %s (%d)",
REQ_TO_STRING (req), len);
else
log_debug ("tunnel_read_request: %s (%d)",
REQ_TO_STRING (req), len);
return 1;
}
ssize_t
tunnel_read (Tunnel *tunnel, void *data, size_t length)
{
enum tunnel_request req;
size_t len;
ssize_t n;
if (tunnel->buf_len > 0)
{
n = min (tunnel->buf_len, length);
memcpy (data, tunnel->buf_ptr, n);
tunnel->buf_ptr += n;
tunnel->buf_len -= n;
return n;
}
if (tunnel->in_fd == -1)
{
if (tunnel_is_client (tunnel))
{
if (tunnel_in_connect (tunnel) == -1)
return -1;
}
else
{
#if 1
if (tunnel_accept (tunnel) == -1)
return -1;
#else
errno = EAGAIN;
return -1;
#endif
}
errno = EAGAIN;
return -1;
}
if (tunnel->out_fd == -1 && tunnel_is_server (tunnel))
{
tunnel_accept (tunnel);
errno = EAGAIN;
return -1;
}
if (tunnel_read_request (tunnel, &req, tunnel->buf, &len) <= 0)
{
log_annoying ("tunnel_read_request returned <= 0, returning -1");
return -1;
}
switch (req)
{
case TUNNEL_OPEN:
/* do something with tunnel->buf */
break;
case TUNNEL_DATA:
tunnel->buf_ptr = tunnel->buf;
tunnel->buf_len = len;
tunnel->in_total_data += len;
log_verbose ("tunnel_read: in_total_data = %u", tunnel->in_total_data);
return tunnel_read (tunnel, data, length);
case TUNNEL_PADDING:
/* discard data */
break;
case TUNNEL_PAD1:
/* do nothing */
break;
case TUNNEL_ERROR:
tunnel->buf[len] = 0;
log_error ("tunnel_read: received error: %s", tunnel->buf);
errno = EIO;
return -1;
case TUNNEL_CLOSE:
return 0;
case TUNNEL_DISCONNECT:
tunnel_in_disconnect (tunnel);
if (tunnel_is_client (tunnel)
&& tunnel_in_connect (tunnel) == -1)
return -1;
errno = EAGAIN;
return -1;
default:
log_error ("tunnel_read: protocol error: unknown request 0x%02x", req);
errno = EINVAL;
return -1;
}
errno = EAGAIN;
return -1;
}
int
tunnel_pollin_fd (Tunnel *tunnel)
{
if (tunnel_is_server (tunnel) &&
(tunnel->in_fd == -1 || tunnel->out_fd == -1))
{
if (tunnel->in_fd == -1)
log_verbose ("tunnel_pollin_fd: in_fd = -1; returning server_socket = %d",
tunnel->server_socket);
else
log_verbose ("tunnel_pollin_fd: out_fd = -1; returning server_socket = %d",
tunnel->server_socket);
return tunnel->server_socket;
}
else if (tunnel->in_fd != -1)
return tunnel->in_fd;
else
{
log_error ("tunnel_pollin_fd: returning -1");
return -1;