/***************************************************************************
* _ _ ____ _
* Project ___| | | | _ \| |
* / __| | | | |_) | |
* | (__| |_| | _ <| |___
* \___|\___/|_| \_\_____|
*
* Copyright (C) 1998 - 2005, Daniel Stenberg, <daniel@haxx.se>, et al.
*
* This software is licensed as described in the file COPYING, which
* you should have received as part of this distribution. The terms
* are also available at http://curl.haxx.se/docs/copyright.html.
*
* You may opt to use, copy, modify, merge, publish, distribute and/or sell
* copies of the Software, and permit persons to whom the Software is
* furnished to do so, under the terms of the COPYING file.
*
* This software is distributed on an "AS IS" basis, WITHOUT WARRANTY OF ANY
* KIND, either express or implied.
*
* $Id$
***************************************************************************/
/* Purpose
*
* 1. Accept a TCP connection on a custom port (ipv4 or ipv6).
*
* 2. Get commands on STDIN. Pass data on to the TCP stream.
* Get data from TCP stream and pass on to STDOUT.
*
* This program is made to perform all the socket/stream/connection stuff for
* the test suite's (perl) FTP server. Previously the perl code did all of
* this by its own, but I decided to let this program do the socket layer
* because of several things:
*
* o We want the perl code to work with rather old perl installations, thus
* we cannot use recent perl modules or features.
*
* o We want IPv6 support for systems that provide it, and doing optional IPv6
* support in perl seems if not impossible so at least awkward.
*
* o We want FTP-SSL support, which means that a connection that starts with
* plain sockets needs to be able to "go SSL" in the midst. This would also
* require some nasty perl stuff I'd rather avoid.
*
* (Source originally based on sws.c)
*/
#include "setup.h" /* portability help from the lib directory */
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <stdarg.h>
#include <signal.h>
#include <time.h>
#include <ctype.h>
#include <sys/time.h>
#include <sys/types.h>
#ifdef HAVE_UNISTD_H
#include <unistd.h>
#endif
#ifdef HAVE_SYS_SOCKET_H
#include <sys/socket.h>
#endif
#ifdef HAVE_NETINET_IN_H
#include <netinet/in.h>
#endif
#ifdef _XOPEN_SOURCE_EXTENDED
/* This define is "almost" required to build on HPUX 11 */
#include <arpa/inet.h>
#endif
#ifdef HAVE_NETDB_H
#include <netdb.h>
#endif
#include "curlx.h" /* from the private lib dir */
#include "getpart.h"
#include "inet_pton.h"
#ifndef FALSE
#define FALSE 0
#endif
#ifndef TRUE
#define TRUE 1
#endif
#if defined(WIN32) && !defined(__CYGWIN__)
#include <windows.h>
#include <winsock2.h>
#include <process.h>
#define sleep(sec) Sleep ((sec)*1000)
#define EINPROGRESS WSAEINPROGRESS
#define EWOULDBLOCK WSAEWOULDBLOCK
#define EISCONN WSAEISCONN
#define ENOTSOCK WSAENOTSOCK
#define ECONNREFUSED WSAECONNREFUSED
static void win32_cleanup(void);
#if defined(ENABLE_IPV6) && defined(__MINGW32__)
const struct in6_addr in6addr_any = {{ IN6ADDR_ANY_INIT }};
#endif
#endif
/* include memdebug.h last */
#include "memdebug.h"
#define DEFAULT_PORT 8999
#ifndef DEFAULT_LOGFILE
#define DEFAULT_LOGFILE "log/sockfilt.log"
#endif
#ifdef SIGPIPE
static volatile int sigpipe; /* Why? It's not used */
#endif
char *socklogfile = (char *)DEFAULT_LOGFILE;
/*
* ourerrno() returns the errno (or equivalent) on this platform to
* hide platform specific for the function that calls this.
*/
static int ourerrno(void)
{
#ifdef WIN32
return (int)GetLastError();
#else
return errno;
#endif
}
static void logmsg(const char *msg, ...)
{
time_t t = time(NULL);
va_list ap;
struct tm *curr_time = localtime(&t);
char buffer[256]; /* possible overflow if you pass in a huge string */
FILE *logfp;
va_start(ap, msg);
vsprintf(buffer, msg, ap);
va_end(ap);
logfp = fopen(socklogfile, "a");
fprintf(logfp?logfp:stderr, /* write to stderr if the logfile doesn't open */
"%02d:%02d:%02d %s\n",
curr_time->tm_hour,
curr_time->tm_min,
curr_time->tm_sec, buffer);
if(logfp)
fclose(logfp);
}
static void lograw(unsigned char *buffer, int len)
{
char data[120];
int i;
unsigned char *ptr = buffer;
char *optr = data;
int width=0;
for(i=0; i<len; i++) {
sprintf(optr, "%c",
(isgraph(ptr[i]) || ptr[i]==0x20) ?ptr[i]:'.');
optr += 1;
width += 1;
if(width>60) {
logmsg("RAW: '%s'", data);
width = 0;
optr = data;
}
}
if(width)
logmsg("RAW: '%s'", data);
}
#ifdef SIGPIPE
static void sigpipe_handler(int sig)
{
(void)sig; /* prevent warning */
sigpipe = 1;
}
#endif
#if defined(WIN32) && !defined(__CYGWIN__)
#undef perror
#define perror(m) win32_perror(m)
static void win32_perror(const char *msg)
{
char buf[256];
DWORD err = WSAGetLastError();
if (!FormatMessage(FORMAT_MESSAGE_FROM_SYSTEM, NULL, err,
LANG_NEUTRAL, buf, sizeof(buf), NULL))
snprintf(buf, sizeof(buf), "Unknown error %lu (%#lx)", err, err);
if (msg)
fprintf(stderr, "%s: ", msg);
fprintf(stderr, "%s\n", buf);
}
#endif
#if defined(WIN32) && !defined(__CYGWIN__)
static void win32_init(void)
{
WORD wVersionRequested;
WSADATA wsaData;
int err;
wVersionRequested = MAKEWORD(2, 0);
err = WSAStartup(wVersionRequested, &wsaData);
if (err != 0) {
perror("Winsock init failed");
logmsg("Error initialising winsock -- aborting\n");
exit(1);
}
if ( LOBYTE( wsaData.wVersion ) != 2 ||
HIBYTE( wsaData.wVersion ) != 0 ) {
WSACleanup();
perror("Winsock init failed");
logmsg("No suitable winsock.dll found -- aborting\n");
exit(1);
}
}
static void win32_cleanup(void)
{
WSACleanup();
}
#endif
char use_ipv6=FALSE;
unsigned short port = DEFAULT_PORT;
unsigned short connectport = 0; /* if non-zero, we activate this mode */
enum sockmode {
PASSIVE_LISTEN, /* as a server waiting for connections */
PASSIVE_CONNECT, /* as a server, connected to a client */
ACTIVE /* as a client, connected to a server */
};
/*
sockfdp is a pointer to an established stream or CURL_SOCKET_BAD
if sockfd is CURL_SOCKET_BAD, listendfd is a listening socket we must
accept()
*/
static int juggle(curl_socket_t *sockfdp,
curl_socket_t listenfd,
enum sockmode *mode)
{
struct timeval timeout;
fd_set fds_read;
fd_set fds_write;
fd_set fds_err;
curl_socket_t maxfd;
int r;
unsigned char buffer[256]; /* FIX: bigger buffer */
char data[256];
int sockfd;
timeout.tv_sec = 120;
timeout.tv_usec = 0;
FD_ZERO(&fds_read);
FD_ZERO(&fds_write);
FD_ZERO(&fds_err);
FD_SET(fileno(stdin), &fds_read);
switch(*mode) {
case PASSIVE_LISTEN:
/* server mode */
sockfd = listenfd;
logmsg("waiting for a client to connect on socket %d", (int)sockfd);
/* there's always a socket to wait for */
FD_SET(sockfd, &fds_read);
maxfd = sockfd;
break;
case PASSIVE_CONNECT:
sockfd = *sockfdp;
logmsg("waiting for data from client on socket %d", (int)sockfd);
/* there's always a socket to wait for */
FD_SET(sockfd, &fds_read);
maxfd = sockfd;
break;
case ACTIVE:
sockfd = *sockfdp;
/* sockfd turns CURL_SOCKET_BAD when our connection has been closed */
if(sockfd != CURL_SOCKET_BAD) {
FD_SET(sockfd, &fds_read);
maxfd = sockfd;
logmsg("waiting for data from client on socket %d", (int)sockfd);
}
else {
logmsg("No socket to read on");
maxfd = 0;
}
break;
}
do {
r = select(maxfd + 1, &fds_read, &fds_write, &fds_err, &timeout);
} while((r == -1) && (ourerrno() == EINTR));
logmsg("select() returned %d", r);
switch(r) {
case -1:
return FALSE;
case 0: /* timeout! */
return TRUE;
}
if(FD_ISSET(fileno(stdin), &fds_read)) {
size_t nread;
logmsg("data on stdin");
/* read from stdin, commands/data to be dealt with and possibly passed on
to the socket
protocol:
4 letter command + LF [mandatory]
4-digit hexadecimal data length + LF [if the command takes data]
data [the data being as long as set above]
Commands:
DATA - plain pass-thru data
*/
nread = read(fileno(stdin), buffer, 5);
if(5 == nread) {
logmsg("Received command %c%c%c%c",
buffer[0], buffer[1], buffer[2], buffer[3] );
if(!memcmp("PING", buffer, 4)) {
/* send reply on stdout, just proving we are alive */
write(fileno(stdout), "PONG\n", 5);
}
else if(!memcmp("PORT", buffer, 4)) {
/* question asking us what PORT number we are listening to.
Replies with PORT with "IPv[num]/[port]" */
sprintf((char *)buffer, "IPv%d/%d\n", use_ipv6?6:4, port);
r = strlen((char *)buffer);
sprintf(data, "PORT\n%04x\n", r);
write(fileno(stdout), data, 10);
write(fileno(stdout), buffer, r);
}
else if(!memcmp("QUIT", buffer, 4)) {
/* just die */
logmsg("quits");
exit(0);
}
else if(!memcmp("DATA", buffer, 4)) {
/* data IN => data OUT */
long len;
if(5 != read(fileno(stdin), buffer, 5))
return FALSE;
len = strtol((char *)buffer, NULL, 16);
if(len != read(fileno(stdin), buffer, len))
return FALSE;
logmsg("> %d bytes data, server => client", len);
lograw(buffer, len);
if(*mode == PASSIVE_LISTEN) {
logmsg(".., but we are disconnected!");
write(fileno(stdout), "DISC\n", 5);
}
else
/* send away on the socket */
swrite(sockfd, buffer, len);
}
else if(!memcmp("DISC", buffer, 4)) {
/* disconnect! */
write(fileno(stdout), "DISC\n", 5);
if(sockfd != CURL_SOCKET_BAD) {
logmsg("====> Client forcibly disconnected");
sclose(sockfd);
*sockfdp = CURL_SOCKET_BAD;
}
else
logmsg("attempt to close already dead connection");
return TRUE;
}
}
else {
logmsg("read %d from stdin, exiting", (int)nread);
exit(0);
}
}
if((sockfd != CURL_SOCKET_BAD) && (FD_ISSET(sockfd, &fds_read)) ) {
logmsg("data on socket");
if(*mode == PASSIVE_LISTEN) {
/* there's no stream set up yet, this is an indication that there's a
client connecting. */
sockfd = accept(sockfd, NULL, NULL);
if(-1 == sockfd)
logmsg("accept() failed\n");
else {
logmsg("====> Client connect");
write(fileno(stdout), "CNCT\n", 5);
*sockfdp = sockfd; /* store the new socket */
*mode = PASSIVE_CONNECT; /* we have connected */
}
return TRUE;
}
/* read from socket, pass on data to stdout */
r = sread(sockfd, buffer, sizeof(buffer));
if(r <= 0) {
logmsg("====> Client disconnect");
write(fileno(stdout), "DISC\n", 5);
sclose(sockfd);
*sockfdp = CURL_SOCKET_BAD;
if(*mode == PASSIVE_CONNECT)
*mode = PASSIVE_LISTEN;
return TRUE;
}
sprintf(data, "DATA\n%04x\n", r);
write(fileno(stdout), data, 10);
write(fileno(stdout), buffer, r);
logmsg("< %d bytes data, client => server", r);
lograw(buffer, r);
}
return TRUE;
}
int main(int argc, char *argv[])
{
struct sockaddr_in me;
#ifdef ENABLE_IPV6
struct sockaddr_in6 me6;
#endif /* ENABLE_IPV6 */
int sock;
int msgsock = CURL_SOCKET_BAD; /* no stream socket yet */
int flag;
FILE *pidfile;
char *pidname= (char *)".sockfilt.pid";
int rc;
int arg=1;
bool ok = FALSE;
enum sockmode mode = PASSIVE_LISTEN; /* default */
while(argc>arg) {
if(!strcmp("--version", argv[arg])) {
printf("sockfilt IPv4%s\n",
#ifdef ENABLE_IPV6
"/IPv6"
#else
""
#endif
);
return 0;
}
else if(!strcmp("--pidfile", argv[arg])) {
arg++;
if(argc>arg)
pidname = argv[arg++];
}
else if(!strcmp("--logfile", argv[arg])) {
arg++;
if(argc>arg)
socklogfile = argv[arg++];
}
else if(!strcmp("--ipv6", argv[arg])) {
#ifdef ENABLE_IPV6
use_ipv6=TRUE;
#endif
arg++;
}
else if(!strcmp("--ipv4", argv[arg])) {
/* for completeness, we support this option as well */
use_ipv6=FALSE;
arg++;
}
else if(!strcmp("--port", argv[arg])) {
arg++;
if(argc>arg) {
port = (unsigned short)atoi(argv[arg]);
arg++;
}
}
else if(!strcmp("--connect", argv[arg])) {
/* Asked to actively connect to the specified local port instead of
doing a passive server-style listening. */
arg++;
if(argc>arg) {
connectport = (unsigned short)atoi(argv[arg]);
arg++;
}
}
else {
puts("Usage: sockfilt [option]\n"
" --version\n"
" --logfile [file]\n"
" --pidfile [file]\n"
" --ipv4\n"
" --ipv6\n"
" --port [port]");
exit(0);
}
}
#if defined(WIN32) && !defined(__GNUC__) || defined(__MINGW32__)
win32_init();
atexit(win32_cleanup);
#else
#ifdef SIGPIPE
#ifdef HAVE_SIGNAL
signal(SIGPIPE, sigpipe_handler);
#endif
#ifdef HAVE_SIGINTERRUPT
siginterrupt(SIGPIPE, 1);
#endif
#endif
#endif
#ifdef ENABLE_IPV6
if(!use_ipv6)
#endif
sock = socket(AF_INET, SOCK_STREAM, 0);
#ifdef ENABLE_IPV6
else
sock = socket(AF_INET6, SOCK_STREAM, 0);
#endif
if (sock < 0) {
perror("opening stream socket");
logmsg("Error opening socket");
exit(1);
}
if(connectport) {
/* Active mode, we should connect to the given port number */
mode = ACTIVE;
#ifdef ENABLE_IPV6
if(!use_ipv6) {
#endif
memset(&me, 0, sizeof(me));
me.sin_family = AF_INET;
me.sin_port = htons(connectport);
me.sin_addr.s_addr = INADDR_ANY;
Curl_inet_pton(AF_INET, "127.0.0.1", &me.sin_addr);
rc = connect(sock, (struct sockaddr *) &me, sizeof(me));
#ifdef ENABLE_IPV6
}
else {
memset(&me6, 0, sizeof(me6));
me6.sin6_family = AF_INET6;
me6.sin6_port = htons(connectport);
Curl_inet_pton(AF_INET, "::1", &me6.sin6_addr);
rc = connect(sock, (struct sockaddr *) &me6, sizeof(me6));
}
#endif /* ENABLE_IPV6 */
if(rc) {
perror("connecting stream socket");
logmsg("Error connecting to port %d", port);
exit(1);
}
logmsg("====> Client connect");
msgsock = sock; /* use this as stream */
}
else {
/* passive daemon style */
flag = 1;
if (setsockopt
(sock, SOL_SOCKET, SO_REUSEADDR, (const void *) &flag,
sizeof(int)) < 0) {
perror("setsockopt(SO_REUSEADDR)");
}
#ifdef ENABLE_IPV6
if(!use_ipv6) {
#endif
me.sin_family = AF_INET;
me.sin_addr.s_addr = INADDR_ANY;
me.sin_port = htons(port);
rc = bind(sock, (struct sockaddr *) &me, sizeof(me));
#ifdef ENABLE_IPV6
}
else {
memset(&me6, 0, sizeof(struct sockaddr_in6));
me6.sin6_family = AF_INET6;
me6.sin6_addr = in6addr_any;
me6.sin6_port = htons(port);
rc = bind(sock, (struct sockaddr *) &me6, sizeof(me6));
}
#endif /* ENABLE_IPV6 */
if(rc < 0) {
perror("binding stream socket");
logmsg("Error binding socket");
exit(1);
}
if(!port) {
/* The system picked a port number, now figure out which port we actually
got */
/* we succeeded to bind */
struct sockaddr_in add;
socklen_t socksize = sizeof(add);
if(getsockname(sock, (struct sockaddr *) &add,
&socksize)<0) {
fprintf(stderr, "getsockname() failed");
return 1;
}
port = ntohs(add.sin_port);
}
/* start accepting connections */
listen(sock, 0);
}
pidfile = fopen(pidname, "w");
if(pidfile) {
fprintf(pidfile, "%d\n", (int)getpid());
fclose(pidfile);
}
else
fprintf(stderr, "Couldn't write pid file\n");
logmsg("Running IPv%d version",
(use_ipv6?6:4));
if(connectport)
logmsg("Connected to port %d", connectport);
else
logmsg("Listening on port %d", port);
do {
ok = juggle(&msgsock, sock, &mode);
} while(ok);
sclose(sock);
return 0;
}