971 lines
		
	
	
		
			26 KiB
		
	
	
	
		
			C
		
	
	
	
	
	
			
		
		
	
	
			971 lines
		
	
	
		
			26 KiB
		
	
	
	
		
			C
		
	
	
	
	
	
/***************************************************************************
 | 
						|
 *                                  _   _ ____  _
 | 
						|
 *  Project                     ___| | | |  _ \| |
 | 
						|
 *                             / __| | | | |_) | |
 | 
						|
 *                            | (__| |_| |  _ <| |___
 | 
						|
 *                             \___|\___/|_| \_\_____|
 | 
						|
 *
 | 
						|
 * Copyright (C) 1998 - 2008, 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: sockfilt.c,v 1.55 2008-10-01 17:34:25 danf Exp $
 | 
						|
 ***************************************************************************/
 | 
						|
 | 
						|
/* Purpose
 | 
						|
 *
 | 
						|
 * 1. Accept a TCP connection on a custom port (ipv4 or ipv6), or connect
 | 
						|
 *    to a given (localhost) port.
 | 
						|
 *
 | 
						|
 * 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)
 | 
						|
 */
 | 
						|
 | 
						|
/*
 | 
						|
 * Signal handling notes for sockfilt
 | 
						|
 * ----------------------------------
 | 
						|
 *
 | 
						|
 * This program is a single-threaded process.
 | 
						|
 *
 | 
						|
 * This program is intended to be highly portable and as such it must be kept as
 | 
						|
 * simple as possible, due to this the only signal handling mechanisms used will
 | 
						|
 * be those of ANSI C, and used only in the most basic form which is good enough
 | 
						|
 * for the purpose of this program.
 | 
						|
 *
 | 
						|
 * For the above reason and the specific needs of this program signals SIGHUP,
 | 
						|
 * SIGPIPE and SIGALRM will be simply ignored on systems where this can be done.
 | 
						|
 * If possible, signals SIGINT and SIGTERM will be handled by this program as an
 | 
						|
 * indication to cleanup and finish execution as soon as possible.  This will be
 | 
						|
 * achieved with a single signal handler 'exit_signal_handler' for both signals.
 | 
						|
 *
 | 
						|
 * The 'exit_signal_handler' upon the first SIGINT or SIGTERM received signal
 | 
						|
 * will just set to one the global var 'got_exit_signal' storing in global var
 | 
						|
 * 'exit_signal' the signal that triggered this change.
 | 
						|
 *
 | 
						|
 * Nothing fancy that could introduce problems is used, the program at certain
 | 
						|
 * points in its normal flow checks if var 'got_exit_signal' is set and in case
 | 
						|
 * this is true it just makes its way out of loops and functions in structured
 | 
						|
 * and well behaved manner to achieve proper program cleanup and termination.
 | 
						|
 *
 | 
						|
 * Even with the above mechanism implemented it is worthwile to note that other
 | 
						|
 * signals might still be received, or that there might be systems on which it
 | 
						|
 * is not possible to trap and ignore some of the above signals.  This implies
 | 
						|
 * that for increased portability and reliability the program must be coded as
 | 
						|
 * if no signal was being ignored or handled at all.  Enjoy it!
 | 
						|
 */
 | 
						|
 | 
						|
#include "setup.h" /* portability help from the lib directory */
 | 
						|
 | 
						|
#ifdef HAVE_SIGNAL_H
 | 
						|
#include <signal.h>
 | 
						|
#endif
 | 
						|
#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
 | 
						|
 | 
						|
#define ENABLE_CURLX_PRINTF
 | 
						|
/* make the curlx header define all printf() functions to use the curlx_*
 | 
						|
   versions instead */
 | 
						|
#include "curlx.h" /* from the private lib dir */
 | 
						|
#include "getpart.h"
 | 
						|
#include "inet_pton.h"
 | 
						|
#include "util.h"
 | 
						|
 | 
						|
/* include memdebug.h last */
 | 
						|
#include "memdebug.h"
 | 
						|
 | 
						|
#define DEFAULT_PORT 8999
 | 
						|
 | 
						|
#ifndef DEFAULT_LOGFILE
 | 
						|
#define DEFAULT_LOGFILE "log/sockfilt.log"
 | 
						|
#endif
 | 
						|
 | 
						|
const char *serverlogfile = DEFAULT_LOGFILE;
 | 
						|
 | 
						|
static bool verbose = FALSE;
 | 
						|
#ifdef ENABLE_IPV6
 | 
						|
static bool use_ipv6 = FALSE;
 | 
						|
#endif
 | 
						|
static const char *ipv_inuse = "IPv4";
 | 
						|
static unsigned short port = DEFAULT_PORT;
 | 
						|
static 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 */
 | 
						|
  ACTIVE_DISCONNECT  /* as a client, disconnected from server */
 | 
						|
};
 | 
						|
 | 
						|
/* do-nothing macro replacement for systems which lack siginterrupt() */
 | 
						|
 | 
						|
#ifndef HAVE_SIGINTERRUPT
 | 
						|
#define siginterrupt(x,y) do {} while(0)
 | 
						|
#endif
 | 
						|
 | 
						|
/* vars used to keep around previous signal handlers */
 | 
						|
 | 
						|
typedef RETSIGTYPE (*SIGHANDLER_T)(int);
 | 
						|
 | 
						|
static SIGHANDLER_T old_sighup_handler  = SIG_ERR;
 | 
						|
static SIGHANDLER_T old_sigpipe_handler = SIG_ERR;
 | 
						|
static SIGHANDLER_T old_sigalrm_handler = SIG_ERR;
 | 
						|
static SIGHANDLER_T old_sigint_handler  = SIG_ERR;
 | 
						|
static SIGHANDLER_T old_sigterm_handler = SIG_ERR;
 | 
						|
 | 
						|
/* var which if set indicates that the program should finish execution */
 | 
						|
 | 
						|
SIG_ATOMIC_T got_exit_signal = 0;
 | 
						|
 | 
						|
/* if next is set indicates the first signal handled in exit_signal_handler */
 | 
						|
 | 
						|
static volatile int exit_signal = 0;
 | 
						|
 | 
						|
/* signal handler that will be triggered to indicate that the program
 | 
						|
  should finish its execution in a controlled manner as soon as possible.
 | 
						|
  The first time this is called it will set got_exit_signal to one and
 | 
						|
  store in exit_signal the signal that triggered its execution. */
 | 
						|
 | 
						|
static RETSIGTYPE exit_signal_handler(int signum)
 | 
						|
{
 | 
						|
  int old_errno = ERRNO;
 | 
						|
  if(got_exit_signal == 0) {
 | 
						|
    got_exit_signal = 1;
 | 
						|
    exit_signal = signum;
 | 
						|
  }
 | 
						|
  (void)signal(signum, exit_signal_handler);
 | 
						|
  SET_ERRNO(old_errno);
 | 
						|
}
 | 
						|
 | 
						|
static void install_signal_handlers(void)
 | 
						|
{
 | 
						|
#ifdef SIGHUP
 | 
						|
  /* ignore SIGHUP signal */
 | 
						|
  if((old_sighup_handler = signal(SIGHUP, SIG_IGN)) == SIG_ERR)
 | 
						|
    logmsg("cannot install SIGHUP handler: %s", strerror(ERRNO));
 | 
						|
#endif
 | 
						|
#ifdef SIGPIPE
 | 
						|
  /* ignore SIGPIPE signal */
 | 
						|
  if((old_sigpipe_handler = signal(SIGPIPE, SIG_IGN)) == SIG_ERR)
 | 
						|
    logmsg("cannot install SIGPIPE handler: %s", strerror(ERRNO));
 | 
						|
#endif
 | 
						|
#ifdef SIGALRM
 | 
						|
  /* ignore SIGALRM signal */
 | 
						|
  if((old_sigalrm_handler = signal(SIGALRM, SIG_IGN)) == SIG_ERR)
 | 
						|
    logmsg("cannot install SIGALRM handler: %s", strerror(ERRNO));
 | 
						|
#endif
 | 
						|
#ifdef SIGINT
 | 
						|
  /* handle SIGINT signal with our exit_signal_handler */
 | 
						|
  if((old_sigint_handler = signal(SIGINT, exit_signal_handler)) == SIG_ERR)
 | 
						|
    logmsg("cannot install SIGINT handler: %s", strerror(ERRNO));
 | 
						|
  else
 | 
						|
    siginterrupt(SIGINT, 1);
 | 
						|
#endif
 | 
						|
#ifdef SIGTERM
 | 
						|
  /* handle SIGTERM signal with our exit_signal_handler */
 | 
						|
  if((old_sigterm_handler = signal(SIGTERM, exit_signal_handler)) == SIG_ERR)
 | 
						|
    logmsg("cannot install SIGTERM handler: %s", strerror(ERRNO));
 | 
						|
  else
 | 
						|
    siginterrupt(SIGTERM, 1);
 | 
						|
#endif
 | 
						|
}
 | 
						|
 | 
						|
static void restore_signal_handlers(void)
 | 
						|
{
 | 
						|
#ifdef SIGHUP
 | 
						|
  if(SIG_ERR != old_sighup_handler)
 | 
						|
    (void)signal(SIGHUP, old_sighup_handler);
 | 
						|
#endif
 | 
						|
#ifdef SIGPIPE
 | 
						|
  if(SIG_ERR != old_sigpipe_handler)
 | 
						|
    (void)signal(SIGPIPE, old_sigpipe_handler);
 | 
						|
#endif
 | 
						|
#ifdef SIGALRM
 | 
						|
  if(SIG_ERR != old_sigalrm_handler)
 | 
						|
    (void)signal(SIGALRM, old_sigalrm_handler);
 | 
						|
#endif
 | 
						|
#ifdef SIGINT
 | 
						|
  if(SIG_ERR != old_sigint_handler)
 | 
						|
    (void)signal(SIGINT, old_sigint_handler);
 | 
						|
#endif
 | 
						|
#ifdef SIGTERM
 | 
						|
  if(SIG_ERR != old_sigterm_handler)
 | 
						|
    (void)signal(SIGTERM, old_sigterm_handler);
 | 
						|
#endif
 | 
						|
}
 | 
						|
 | 
						|
/*
 | 
						|
 * fullread is a wrapper around the read() function. This will repeat the call
 | 
						|
 * to read() until it actually has read the complete number of bytes indicated
 | 
						|
 * in nbytes or it fails with a condition that cannot be handled with a simple
 | 
						|
 * retry of the read call.
 | 
						|
 */
 | 
						|
 | 
						|
static ssize_t fullread(int filedes, void *buffer, size_t nbytes)
 | 
						|
{
 | 
						|
  int error;
 | 
						|
  ssize_t rc;
 | 
						|
  ssize_t nread = 0;
 | 
						|
 | 
						|
  do {
 | 
						|
    rc = read(filedes, (unsigned char *)buffer + nread, nbytes - nread);
 | 
						|
 | 
						|
    if(got_exit_signal) {
 | 
						|
      logmsg("signalled to die");
 | 
						|
      return -1;
 | 
						|
    }
 | 
						|
 | 
						|
    if(rc < 0) {
 | 
						|
      error = ERRNO;
 | 
						|
      if((error == EINTR) || (error == EAGAIN))
 | 
						|
        continue;
 | 
						|
      logmsg("unrecoverable read() failure: %s", strerror(error));
 | 
						|
      return -1;
 | 
						|
    }
 | 
						|
 | 
						|
    if(rc == 0) {
 | 
						|
      logmsg("got 0 reading from stdin");
 | 
						|
      return 0;
 | 
						|
    }
 | 
						|
 | 
						|
    nread += rc;
 | 
						|
 | 
						|
  } while((size_t)nread < nbytes);
 | 
						|
 | 
						|
  if(verbose)
 | 
						|
    logmsg("read %zd bytes", nread);
 | 
						|
 | 
						|
  return nread;
 | 
						|
}
 | 
						|
 | 
						|
/*
 | 
						|
 * fullwrite is a wrapper around the write() function. This will repeat the
 | 
						|
 * call to write() until it actually has written the complete number of bytes
 | 
						|
 * indicated in nbytes or it fails with a condition that cannot be handled
 | 
						|
 * with a simple retry of the write call.
 | 
						|
 */
 | 
						|
 | 
						|
static ssize_t fullwrite(int filedes, const void *buffer, size_t nbytes)
 | 
						|
{
 | 
						|
  int error;
 | 
						|
  ssize_t wc;
 | 
						|
  ssize_t nwrite = 0;
 | 
						|
 | 
						|
  do {
 | 
						|
    wc = write(filedes, (unsigned char *)buffer + nwrite, nbytes - nwrite);
 | 
						|
 | 
						|
    if(got_exit_signal) {
 | 
						|
      logmsg("signalled to die");
 | 
						|
      return -1;
 | 
						|
    }
 | 
						|
 | 
						|
    if(wc < 0) {
 | 
						|
      error = ERRNO;
 | 
						|
      if((error == EINTR) || (error == EAGAIN))
 | 
						|
        continue;
 | 
						|
      logmsg("unrecoverable write() failure: %s", strerror(error));
 | 
						|
      return -1;
 | 
						|
    }
 | 
						|
 | 
						|
    if(wc == 0) {
 | 
						|
      logmsg("put 0 writing to stdout");
 | 
						|
      return 0;
 | 
						|
    }
 | 
						|
 | 
						|
    nwrite += wc;
 | 
						|
 | 
						|
  } while((size_t)nwrite < nbytes);
 | 
						|
 | 
						|
  if(verbose)
 | 
						|
    logmsg("wrote %zd bytes", nwrite);
 | 
						|
 | 
						|
  return nwrite;
 | 
						|
}
 | 
						|
 | 
						|
/*
 | 
						|
 * read_stdin tries to read from stdin nbytes into the given buffer. This is a
 | 
						|
 * blocking function that will only return TRUE when nbytes have actually been
 | 
						|
 * read or FALSE when an unrecoverable error has been detected. Failure of this
 | 
						|
 * function is an indication that the sockfilt process should terminate.
 | 
						|
 */
 | 
						|
 | 
						|
static bool read_stdin(void *buffer, size_t nbytes)
 | 
						|
{
 | 
						|
  ssize_t nread = fullread(fileno(stdin), buffer, nbytes);
 | 
						|
  if(nread != (ssize_t)nbytes) {
 | 
						|
    logmsg("exiting...");
 | 
						|
    return FALSE;
 | 
						|
  }
 | 
						|
  return TRUE;
 | 
						|
}
 | 
						|
 | 
						|
/*
 | 
						|
 * write_stdout tries to write to stdio nbytes from the given buffer. This is a
 | 
						|
 * blocking function that will only return TRUE when nbytes have actually been
 | 
						|
 * written or FALSE when an unrecoverable error has been detected. Failure of
 | 
						|
 * this function is an indication that the sockfilt process should terminate.
 | 
						|
 */
 | 
						|
 | 
						|
static bool write_stdout(const void *buffer, size_t nbytes)
 | 
						|
{
 | 
						|
  ssize_t nwrite = fullwrite(fileno(stdout), buffer, nbytes);
 | 
						|
  if(nwrite != (ssize_t)nbytes) {
 | 
						|
    logmsg("exiting...");
 | 
						|
    return FALSE;
 | 
						|
  }
 | 
						|
  return TRUE;
 | 
						|
}
 | 
						|
 | 
						|
static void lograw(unsigned char *buffer, ssize_t len)
 | 
						|
{
 | 
						|
  char data[120];
 | 
						|
  ssize_t i;
 | 
						|
  unsigned char *ptr = buffer;
 | 
						|
  char *optr = data;
 | 
						|
  ssize_t width=0;
 | 
						|
 | 
						|
  for(i=0; i<len; i++) {
 | 
						|
    switch(ptr[i]) {
 | 
						|
    case '\n':
 | 
						|
      sprintf(optr, "\\n");
 | 
						|
      width += 2;
 | 
						|
      optr += 2;
 | 
						|
      break;
 | 
						|
    case '\r':
 | 
						|
      sprintf(optr, "\\r");
 | 
						|
      width += 2;
 | 
						|
      optr += 2;
 | 
						|
      break;
 | 
						|
    default:
 | 
						|
      sprintf(optr, "%c", (ISGRAPH(ptr[i]) || ptr[i]==0x20) ?ptr[i]:'.');
 | 
						|
      width++;
 | 
						|
      optr++;
 | 
						|
      break;
 | 
						|
    }
 | 
						|
 | 
						|
    if(width>60) {
 | 
						|
      logmsg("'%s'", data);
 | 
						|
      width = 0;
 | 
						|
      optr = data;
 | 
						|
    }
 | 
						|
  }
 | 
						|
  if(width)
 | 
						|
    logmsg("'%s'", data);
 | 
						|
}
 | 
						|
 | 
						|
/*
 | 
						|
  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 bool 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 sockfd = CURL_SOCKET_BAD;
 | 
						|
  curl_socket_t maxfd = CURL_SOCKET_BAD;
 | 
						|
  ssize_t rc;
 | 
						|
  ssize_t nread_socket;
 | 
						|
  ssize_t bytes_written;
 | 
						|
  ssize_t buffer_len;
 | 
						|
  int error = 0;
 | 
						|
 | 
						|
 /* 'buffer' is this excessively large only to be able to support things like
 | 
						|
    test 1003 which tests exceedingly large server response lines */
 | 
						|
  unsigned char buffer[17010];
 | 
						|
  char data[16];
 | 
						|
 | 
						|
  if(got_exit_signal) {
 | 
						|
    logmsg("signalled to die, exiting...");
 | 
						|
    return FALSE;
 | 
						|
  }
 | 
						|
 | 
						|
#ifdef HAVE_GETPPID
 | 
						|
  /* As a last resort, quit if sockfilt process becomes orphan. Just in case
 | 
						|
     parent ftpserver process has died without killing its sockfilt children */
 | 
						|
  if(getppid() <= 1) {
 | 
						|
    logmsg("process becomes orphan, exiting");
 | 
						|
    return FALSE;
 | 
						|
  }
 | 
						|
#endif
 | 
						|
 | 
						|
  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;
 | 
						|
    /* there's always a socket to wait for */
 | 
						|
    FD_SET(sockfd, &fds_read);
 | 
						|
    maxfd = sockfd;
 | 
						|
    break;
 | 
						|
 | 
						|
  case PASSIVE_CONNECT:
 | 
						|
 | 
						|
    sockfd = *sockfdp;
 | 
						|
    if(CURL_SOCKET_BAD == sockfd) {
 | 
						|
      /* eeek, we are supposedly connected and then this cannot be -1 ! */
 | 
						|
      logmsg("socket is -1! on %s:%d", __FILE__, __LINE__);
 | 
						|
      maxfd = 0; /* stdin */
 | 
						|
    }
 | 
						|
    else {
 | 
						|
      /* 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(CURL_SOCKET_BAD != sockfd) {
 | 
						|
      FD_SET(sockfd, &fds_read);
 | 
						|
      maxfd = sockfd;
 | 
						|
    }
 | 
						|
    else {
 | 
						|
      logmsg("No socket to read on");
 | 
						|
      maxfd = 0;
 | 
						|
    }
 | 
						|
    break;
 | 
						|
 | 
						|
  case ACTIVE_DISCONNECT:
 | 
						|
 | 
						|
    logmsg("disconnected, no socket to read on");
 | 
						|
    maxfd = 0;
 | 
						|
    sockfd = CURL_SOCKET_BAD;
 | 
						|
    break;
 | 
						|
 | 
						|
  } /* switch(*mode) */
 | 
						|
 | 
						|
 | 
						|
  do {
 | 
						|
 | 
						|
    rc = select((int)maxfd + 1, &fds_read, &fds_write, &fds_err, &timeout);
 | 
						|
 | 
						|
    if(got_exit_signal) {
 | 
						|
      logmsg("signalled to die, exiting...");
 | 
						|
      return FALSE;
 | 
						|
    }
 | 
						|
 | 
						|
  } while((rc == -1) && ((error = SOCKERRNO) == EINTR));
 | 
						|
 | 
						|
  if(rc < 0) {
 | 
						|
    logmsg("select() failed with error: (%d) %s",
 | 
						|
           error, strerror(error));
 | 
						|
    return FALSE;
 | 
						|
  }
 | 
						|
 | 
						|
  if(rc == 0)
 | 
						|
    /* timeout */
 | 
						|
    return TRUE;
 | 
						|
 | 
						|
 | 
						|
  if(FD_ISSET(fileno(stdin), &fds_read)) {
 | 
						|
    /* 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
 | 
						|
    */
 | 
						|
 | 
						|
    if(!read_stdin(buffer, 5))
 | 
						|
      return FALSE;
 | 
						|
 | 
						|
    logmsg("Received %c%c%c%c (on stdin)",
 | 
						|
           buffer[0], buffer[1], buffer[2], buffer[3] );
 | 
						|
 | 
						|
    if(!memcmp("PING", buffer, 4)) {
 | 
						|
      /* send reply on stdout, just proving we are alive */
 | 
						|
      if(!write_stdout("PONG\n", 5))
 | 
						|
        return FALSE;
 | 
						|
    }
 | 
						|
 | 
						|
    else if(!memcmp("PORT", buffer, 4)) {
 | 
						|
      /* Question asking us what PORT number we are listening to.
 | 
						|
         Replies to PORT with "IPv[num]/[port]" */
 | 
						|
      sprintf((char *)buffer, "%s/%d\n", ipv_inuse, (int)port);
 | 
						|
      buffer_len = (ssize_t)strlen((char *)buffer);
 | 
						|
      snprintf(data, sizeof(data), "PORT\n%04x\n", buffer_len);
 | 
						|
      if(!write_stdout(data, 10))
 | 
						|
        return FALSE;
 | 
						|
      if(!write_stdout(buffer, buffer_len))
 | 
						|
        return FALSE;
 | 
						|
    }
 | 
						|
    else if(!memcmp("QUIT", buffer, 4)) {
 | 
						|
      /* just die */
 | 
						|
      logmsg("quits");
 | 
						|
      return FALSE;
 | 
						|
    }
 | 
						|
    else if(!memcmp("DATA", buffer, 4)) {
 | 
						|
      /* data IN => data OUT */
 | 
						|
 | 
						|
      if(!read_stdin(buffer, 5))
 | 
						|
        return FALSE;
 | 
						|
 | 
						|
      buffer[5] = '\0';
 | 
						|
 | 
						|
      buffer_len = (ssize_t)strtol((char *)buffer, NULL, 16);
 | 
						|
      if (buffer_len > (ssize_t)sizeof(buffer)) {
 | 
						|
        logmsg("ERROR: Buffer size (%zu bytes) too small for data size "
 | 
						|
               "(%zd bytes)", sizeof(buffer), buffer_len);
 | 
						|
        return FALSE;
 | 
						|
      }
 | 
						|
      logmsg("> %zd bytes data, server => client", buffer_len);
 | 
						|
 | 
						|
      if(!read_stdin(buffer, buffer_len))
 | 
						|
        return FALSE;
 | 
						|
 | 
						|
      lograw(buffer, buffer_len);
 | 
						|
 | 
						|
      if(*mode == PASSIVE_LISTEN) {
 | 
						|
        logmsg("*** We are disconnected!");
 | 
						|
        if(!write_stdout("DISC\n", 5))
 | 
						|
          return FALSE;
 | 
						|
      }
 | 
						|
      else {
 | 
						|
        /* send away on the socket */
 | 
						|
        bytes_written = swrite(sockfd, buffer, buffer_len);
 | 
						|
        if(bytes_written != buffer_len) {
 | 
						|
          logmsg("Not all data was sent. Bytes to send: %zd sent: %zd",
 | 
						|
                 buffer_len, bytes_written);
 | 
						|
        }
 | 
						|
      }
 | 
						|
    }
 | 
						|
    else if(!memcmp("DISC", buffer, 4)) {
 | 
						|
      /* disconnect! */
 | 
						|
      if(!write_stdout("DISC\n", 5))
 | 
						|
        return FALSE;
 | 
						|
      if(sockfd != CURL_SOCKET_BAD) {
 | 
						|
        logmsg("====> Client forcibly disconnected");
 | 
						|
        sclose(sockfd);
 | 
						|
        *sockfdp = CURL_SOCKET_BAD;
 | 
						|
        if(*mode == PASSIVE_CONNECT)
 | 
						|
          *mode = PASSIVE_LISTEN;
 | 
						|
        else
 | 
						|
          *mode = ACTIVE_DISCONNECT;
 | 
						|
      }
 | 
						|
      else
 | 
						|
        logmsg("attempt to close already dead connection");
 | 
						|
      return TRUE;
 | 
						|
    }
 | 
						|
  }
 | 
						|
 | 
						|
 | 
						|
  if((sockfd != CURL_SOCKET_BAD) && (FD_ISSET(sockfd, &fds_read)) ) {
 | 
						|
 | 
						|
    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(CURL_SOCKET_BAD == sockfd)
 | 
						|
        logmsg("accept() failed");
 | 
						|
      else {
 | 
						|
        logmsg("====> Client connect");
 | 
						|
        if(!write_stdout("CNCT\n", 5))
 | 
						|
          return FALSE;
 | 
						|
        *sockfdp = sockfd; /* store the new socket */
 | 
						|
        *mode = PASSIVE_CONNECT; /* we have connected */
 | 
						|
      }
 | 
						|
      return TRUE;
 | 
						|
    }
 | 
						|
 | 
						|
    /* read from socket, pass on data to stdout */
 | 
						|
    nread_socket = sread(sockfd, buffer, sizeof(buffer));
 | 
						|
 | 
						|
    if(nread_socket <= 0) {
 | 
						|
      logmsg("====> Client disconnect");
 | 
						|
      if(!write_stdout("DISC\n", 5))
 | 
						|
        return FALSE;
 | 
						|
      sclose(sockfd);
 | 
						|
      *sockfdp = CURL_SOCKET_BAD;
 | 
						|
      if(*mode == PASSIVE_CONNECT)
 | 
						|
        *mode = PASSIVE_LISTEN;
 | 
						|
      else
 | 
						|
        *mode = ACTIVE_DISCONNECT;
 | 
						|
      return TRUE;
 | 
						|
    }
 | 
						|
 | 
						|
    snprintf(data, sizeof(data), "DATA\n%04x\n", nread_socket);
 | 
						|
    if(!write_stdout(data, 10))
 | 
						|
      return FALSE;
 | 
						|
    if(!write_stdout(buffer, nread_socket))
 | 
						|
      return FALSE;
 | 
						|
 | 
						|
    logmsg("< %zd bytes data, client => server", nread_socket);
 | 
						|
    lograw(buffer, nread_socket);
 | 
						|
  }
 | 
						|
 | 
						|
  return TRUE;
 | 
						|
}
 | 
						|
 | 
						|
static curl_socket_t sockdaemon(curl_socket_t sock,
 | 
						|
                                unsigned short *listenport)
 | 
						|
{
 | 
						|
  /* passive daemon style */
 | 
						|
  struct sockaddr_in me;
 | 
						|
#ifdef ENABLE_IPV6
 | 
						|
  struct sockaddr_in6 me6;
 | 
						|
#endif /* ENABLE_IPV6 */
 | 
						|
  int flag = 1;
 | 
						|
  int rc;
 | 
						|
  int totdelay = 0;
 | 
						|
  int maxretr = 10;
 | 
						|
  int delay= 20;
 | 
						|
  int attempt = 0;
 | 
						|
  int error = 0;
 | 
						|
 | 
						|
  do {
 | 
						|
    attempt++;
 | 
						|
    rc = setsockopt(sock, SOL_SOCKET, SO_REUSEADDR,
 | 
						|
         (void *)&flag, sizeof(flag));
 | 
						|
    if(rc) {
 | 
						|
      error = SOCKERRNO;
 | 
						|
      if(maxretr) {
 | 
						|
        rc = wait_ms(delay);
 | 
						|
        if(rc) {
 | 
						|
          /* should not happen */
 | 
						|
          error = SOCKERRNO;
 | 
						|
          logmsg("wait_ms() failed: (%d) %s", error, strerror(error));
 | 
						|
          sclose(sock);
 | 
						|
          return CURL_SOCKET_BAD;
 | 
						|
        }
 | 
						|
        if(got_exit_signal) {
 | 
						|
          logmsg("signalled to die, exiting...");
 | 
						|
          sclose(sock);
 | 
						|
          return CURL_SOCKET_BAD;
 | 
						|
        }
 | 
						|
        totdelay += delay;
 | 
						|
        delay *= 2; /* double the sleep for next attempt */
 | 
						|
      }
 | 
						|
    }
 | 
						|
  } while(rc && maxretr--);
 | 
						|
 | 
						|
  if(rc) {
 | 
						|
    logmsg("setsockopt(SO_REUSEADDR) failed %d times in %d ms. Error: (%d) %s",
 | 
						|
           attempt, totdelay, error, strerror(error));
 | 
						|
    logmsg("Continuing anyway...");
 | 
						|
  }
 | 
						|
 | 
						|
#ifdef ENABLE_IPV6
 | 
						|
  if(!use_ipv6) {
 | 
						|
#endif
 | 
						|
    memset(&me, 0, sizeof(me));
 | 
						|
    me.sin_family = AF_INET;
 | 
						|
    me.sin_addr.s_addr = INADDR_ANY;
 | 
						|
    me.sin_port = htons(*listenport);
 | 
						|
    rc = bind(sock, (struct sockaddr *) &me, sizeof(me));
 | 
						|
#ifdef ENABLE_IPV6
 | 
						|
  }
 | 
						|
  else {
 | 
						|
    memset(&me6, 0, sizeof(me6));
 | 
						|
    me6.sin6_family = AF_INET6;
 | 
						|
    me6.sin6_addr = in6addr_any;
 | 
						|
    me6.sin6_port = htons(*listenport);
 | 
						|
    rc = bind(sock, (struct sockaddr *) &me6, sizeof(me6));
 | 
						|
  }
 | 
						|
#endif /* ENABLE_IPV6 */
 | 
						|
  if(rc) {
 | 
						|
    error = SOCKERRNO;
 | 
						|
    logmsg("Error binding socket: (%d) %s", error, strerror(error));
 | 
						|
    sclose(sock);
 | 
						|
    return CURL_SOCKET_BAD;
 | 
						|
  }
 | 
						|
 | 
						|
  if(!*listenport) {
 | 
						|
    /* 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) {
 | 
						|
      error = SOCKERRNO;
 | 
						|
      logmsg("getsockname() failed with error: (%d) %s",
 | 
						|
             error, strerror(error));
 | 
						|
      sclose(sock);
 | 
						|
      return CURL_SOCKET_BAD;
 | 
						|
    }
 | 
						|
    *listenport = ntohs(add.sin_port);
 | 
						|
  }
 | 
						|
 | 
						|
  /* start accepting connections */
 | 
						|
  rc = listen(sock, 5);
 | 
						|
  if(0 != rc) {
 | 
						|
    error = SOCKERRNO;
 | 
						|
    logmsg("listen() failed with error: (%d) %s",
 | 
						|
           error, strerror(error));
 | 
						|
    sclose(sock);
 | 
						|
    return CURL_SOCKET_BAD;
 | 
						|
  }
 | 
						|
 | 
						|
  return sock;
 | 
						|
}
 | 
						|
 | 
						|
 | 
						|
int main(int argc, char *argv[])
 | 
						|
{
 | 
						|
  struct sockaddr_in me;
 | 
						|
#ifdef ENABLE_IPV6
 | 
						|
  struct sockaddr_in6 me6;
 | 
						|
#endif /* ENABLE_IPV6 */
 | 
						|
  curl_socket_t sock = CURL_SOCKET_BAD;
 | 
						|
  curl_socket_t msgsock = CURL_SOCKET_BAD;
 | 
						|
  int wrotepidfile = 0;
 | 
						|
  char *pidname= (char *)".sockfilt.pid";
 | 
						|
  int rc;
 | 
						|
  int error;
 | 
						|
  int arg=1;
 | 
						|
  enum sockmode mode = PASSIVE_LISTEN; /* default */
 | 
						|
  const char *addr = NULL;
 | 
						|
 | 
						|
  while(argc>arg) {
 | 
						|
    if(!strcmp("--version", argv[arg])) {
 | 
						|
      printf("sockfilt IPv4%s\n",
 | 
						|
#ifdef ENABLE_IPV6
 | 
						|
             "/IPv6"
 | 
						|
#else
 | 
						|
             ""
 | 
						|
#endif
 | 
						|
             );
 | 
						|
      return 0;
 | 
						|
    }
 | 
						|
    else if(!strcmp("--verbose", argv[arg])) {
 | 
						|
      verbose = TRUE;
 | 
						|
      arg++;
 | 
						|
    }
 | 
						|
    else if(!strcmp("--pidfile", argv[arg])) {
 | 
						|
      arg++;
 | 
						|
      if(argc>arg)
 | 
						|
        pidname = argv[arg++];
 | 
						|
    }
 | 
						|
    else if(!strcmp("--logfile", argv[arg])) {
 | 
						|
      arg++;
 | 
						|
      if(argc>arg)
 | 
						|
        serverlogfile = argv[arg++];
 | 
						|
    }
 | 
						|
    else if(!strcmp("--ipv6", argv[arg])) {
 | 
						|
#ifdef ENABLE_IPV6
 | 
						|
      ipv_inuse = "IPv6";
 | 
						|
      use_ipv6 = TRUE;
 | 
						|
#endif
 | 
						|
      arg++;
 | 
						|
    }
 | 
						|
    else if(!strcmp("--ipv4", argv[arg])) {
 | 
						|
      /* for completeness, we support this option as well */
 | 
						|
#ifdef ENABLE_IPV6
 | 
						|
      ipv_inuse = "IPv4";
 | 
						|
      use_ipv6 = FALSE;
 | 
						|
#endif
 | 
						|
      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 if(!strcmp("--addr", argv[arg])) {
 | 
						|
      /* Set an IP address to use with --connect; otherwise use localhost */
 | 
						|
      arg++;
 | 
						|
      if(argc>arg) {
 | 
						|
        addr = argv[arg];
 | 
						|
        arg++;
 | 
						|
      }
 | 
						|
    }
 | 
						|
    else {
 | 
						|
      puts("Usage: sockfilt [option]\n"
 | 
						|
           " --version\n"
 | 
						|
           " --verbose\n"
 | 
						|
           " --logfile [file]\n"
 | 
						|
           " --pidfile [file]\n"
 | 
						|
           " --ipv4\n"
 | 
						|
           " --ipv6\n"
 | 
						|
           " --port [port]\n"
 | 
						|
           " --connect [port]\n"
 | 
						|
           " --addr [address]");
 | 
						|
      return 0;
 | 
						|
    }
 | 
						|
  }
 | 
						|
 | 
						|
#ifdef WIN32
 | 
						|
  win32_init();
 | 
						|
  atexit(win32_cleanup);
 | 
						|
#endif
 | 
						|
 | 
						|
  install_signal_handlers();
 | 
						|
 | 
						|
#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(CURL_SOCKET_BAD == sock) {
 | 
						|
    error = SOCKERRNO;
 | 
						|
    logmsg("Error creating socket: (%d) %s",
 | 
						|
           error, strerror(error));
 | 
						|
    goto sockfilt_cleanup;
 | 
						|
  }
 | 
						|
 | 
						|
  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;
 | 
						|
      if (!addr)
 | 
						|
        addr = "127.0.0.1";
 | 
						|
      Curl_inet_pton(AF_INET, addr, &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);
 | 
						|
      if (!addr)
 | 
						|
        addr = "::1";
 | 
						|
      Curl_inet_pton(AF_INET6, addr, &me6.sin6_addr);
 | 
						|
 | 
						|
      rc = connect(sock, (struct sockaddr *) &me6, sizeof(me6));
 | 
						|
    }
 | 
						|
#endif /* ENABLE_IPV6 */
 | 
						|
    if(rc) {
 | 
						|
      error = SOCKERRNO;
 | 
						|
      logmsg("Error connecting to port %hu: (%d) %s",
 | 
						|
             connectport, error, strerror(error));
 | 
						|
      goto sockfilt_cleanup;
 | 
						|
    }
 | 
						|
    logmsg("====> Client connect");
 | 
						|
    msgsock = sock; /* use this as stream */
 | 
						|
  }
 | 
						|
  else {
 | 
						|
    /* passive daemon style */
 | 
						|
    sock = sockdaemon(sock, &port);
 | 
						|
    if(CURL_SOCKET_BAD == sock)
 | 
						|
      goto sockfilt_cleanup;
 | 
						|
    msgsock = CURL_SOCKET_BAD; /* no stream socket yet */
 | 
						|
  }
 | 
						|
 | 
						|
  logmsg("Running %s version", ipv_inuse);
 | 
						|
 | 
						|
  if(connectport)
 | 
						|
    logmsg("Connected to port %hu", connectport);
 | 
						|
  else
 | 
						|
    logmsg("Listening on port %hu", port);
 | 
						|
 | 
						|
  wrotepidfile = write_pidfile(pidname);
 | 
						|
  if(!wrotepidfile)
 | 
						|
    goto sockfilt_cleanup;
 | 
						|
 | 
						|
  while(juggle(&msgsock, sock, &mode));
 | 
						|
 | 
						|
sockfilt_cleanup:
 | 
						|
 | 
						|
  if((msgsock != sock) && (msgsock != CURL_SOCKET_BAD))
 | 
						|
    sclose(msgsock);
 | 
						|
 | 
						|
  if(sock != CURL_SOCKET_BAD)
 | 
						|
    sclose(sock);
 | 
						|
 | 
						|
  if(wrotepidfile)
 | 
						|
    unlink(pidname);
 | 
						|
 | 
						|
  restore_signal_handlers();
 | 
						|
 | 
						|
  if(got_exit_signal) {
 | 
						|
    logmsg("============> sockfilt exits with signal (%d)", exit_signal);
 | 
						|
    /*
 | 
						|
     * To properly set the return status of the process we
 | 
						|
     * must raise the same signal SIGINT or SIGTERM that we
 | 
						|
     * caught and let the old handler take care of it.
 | 
						|
     */
 | 
						|
    raise(exit_signal);
 | 
						|
  }
 | 
						|
 | 
						|
  logmsg("============> sockfilt quits");
 | 
						|
  return 0;
 | 
						|
}
 | 
						|
 |