CMakeLua/Utilities/cmcurl-7.19.0/tests/server/sockfilt.c

   1 /***************************************************************************
   2  *                                  _   _ ____  _
   3  *  Project                     ___| | | |  _ \| |
   4  *                             / __| | | | |_) | |
   5  *                            | (__| |_| |  _ <| |___
   6  *                             \___|\___/|_| \_\_____|
   7  *
   8  * Copyright (C) 1998 - 2008, Daniel Stenberg, <daniel@haxx.se>, et al.
   9  *
  10  * This software is licensed as described in the file COPYING, which
  11  * you should have received as part of this distribution. The terms
  12  * are also available at http://curl.haxx.se/docs/copyright.html.
  13  *
  14  * You may opt to use, copy, modify, merge, publish, distribute and/or sell
  15  * copies of the Software, and permit persons to whom the Software is
  16  * furnished to do so, under the terms of the COPYING file.
  17  *
  18  * This software is distributed on an "AS IS" basis, WITHOUT WARRANTY OF ANY
  19  * KIND, either express or implied.
  20  *
  21  * $Id: sockfilt.c,v 1.1.1.1 2008-09-23 16:32:06 hoffman Exp $
  22  ***************************************************************************/
  23
  24 /* Purpose
  25  *
  26  * 1. Accept a TCP connection on a custom port (ipv4 or ipv6), or connect
  27  *    to a given (localhost) port.
  28  *
  29  * 2. Get commands on STDIN. Pass data on to the TCP stream.
  30  *    Get data from TCP stream and pass on to STDOUT.
  31  *
  32  * This program is made to perform all the socket/stream/connection stuff for
  33  * the test suite's (perl) FTP server. Previously the perl code did all of
  34  * this by its own, but I decided to let this program do the socket layer
  35  * because of several things:
  36  *
  37  * o We want the perl code to work with rather old perl installations, thus
  38  *   we cannot use recent perl modules or features.
  39  *
  40  * o We want IPv6 support for systems that provide it, and doing optional IPv6
  41  *   support in perl seems if not impossible so at least awkward.
  42  *
  43  * o We want FTP-SSL support, which means that a connection that starts with
  44  *   plain sockets needs to be able to "go SSL" in the midst. This would also
  45  *   require some nasty perl stuff I'd rather avoid.
  46  *
  47  * (Source originally based on sws.c)
  48  */
  49
  50 /*
  51  * Signal handling notes for sockfilt
  52  * ----------------------------------
  53  *
  54  * This program is a single-threaded process.
  55  *
  56  * This program is intended to be highly portable and as such it must be kept as
  57  * simple as possible, due to this the only signal handling mechanisms used will
  58  * be those of ANSI C, and used only in the most basic form which is good enough
  59  * for the purpose of this program.
  60  *
  61  * For the above reason and the specific needs of this program signals SIGHUP,
  62  * SIGPIPE and SIGALRM will be simply ignored on systems where this can be done.
  63  * If possible, signals SIGINT and SIGTERM will be handled by this program as an
  64  * indication to cleanup and finish execution as soon as possible.  This will be
  65  * achieved with a single signal handler 'exit_signal_handler' for both signals.
  66  *
  67  * The 'exit_signal_handler' upon the first SIGINT or SIGTERM received signal
  68  * will just set to one the global var 'got_exit_signal' storing in global var
  69  * 'exit_signal' the signal that triggered this change.
  70  *
  71  * Nothing fancy that could introduce problems is used, the program at certain
  72  * points in its normal flow checks if var 'got_exit_signal' is set and in case
  73  * this is true it just makes its way out of loops and functions in structured
  74  * and well behaved manner to achieve proper program cleanup and termination.
  75  *
  76  * Even with the above mechanism implemented it is worthwile to note that other
  77  * signals might still be received, or that there might be systems on which it
  78  * is not possible to trap and ignore some of the above signals.  This implies
  79  * that for increased portability and reliability the program must be coded as
  80  * if no signal was being ignored or handled at all.  Enjoy it!
  81  */
  82
  83 #include "setup.h" /* portability help from the lib directory */
  84
  85 #ifdef HAVE_SIGNAL_H
  86 #include <signal.h>
  87 #endif
  88 #ifdef HAVE_UNISTD_H
  89 #include <unistd.h>
  90 #endif
  91 #ifdef HAVE_SYS_SOCKET_H
  92 #include <sys/socket.h>
  93 #endif
  94 #ifdef HAVE_NETINET_IN_H
  95 #include <netinet/in.h>
  96 #endif
  97 #ifdef _XOPEN_SOURCE_EXTENDED
  98 /* This define is "almost" required to build on HPUX 11 */
  99 #include <arpa/inet.h>
 100 #endif
 101 #ifdef HAVE_NETDB_H
 102 #include <netdb.h>
 103 #endif
 104
 105 #define ENABLE_CURLX_PRINTF
 106 /* make the curlx header define all printf() functions to use the curlx_*
 107    versions instead */
 108 #include "curlx.h" /* from the private lib dir */
 109 #include "getpart.h"
 110 #include "inet_pton.h"
 111 #include "util.h"
 112
 113 /* include memdebug.h last */
 114 #include "memdebug.h"
 115
 116 #define DEFAULT_PORT 8999
 117
 118 #ifndef DEFAULT_LOGFILE
 119 #define DEFAULT_LOGFILE "log/sockfilt.log"
 120 #endif
 121
 122 const char *serverlogfile = (char *)DEFAULT_LOGFILE;
 123
 124 bool verbose = FALSE;
 125 bool use_ipv6 = FALSE;
 126 unsigned short port = DEFAULT_PORT;
 127 unsigned short connectport = 0; /* if non-zero, we activate this mode */
 128
 129 enum sockmode {
 130   PASSIVE_LISTEN,    /* as a server waiting for connections */
 131   PASSIVE_CONNECT,   /* as a server, connected to a client */
 132   ACTIVE,            /* as a client, connected to a server */
 133   ACTIVE_DISCONNECT  /* as a client, disconnected from server */
 134 };
 135
 136 /* do-nothing macro replacement for systems which lack siginterrupt() */
 137
 138 #ifndef HAVE_SIGINTERRUPT
 139 #define siginterrupt(x,y) do {} while(0)
 140 #endif
 141
 142 /* vars used to keep around previous signal handlers */
 143
 144 typedef RETSIGTYPE (*SIGHANDLER_T)(int);
 145
 146 static SIGHANDLER_T old_sighup_handler  = SIG_ERR;
 147 static SIGHANDLER_T old_sigpipe_handler = SIG_ERR;
 148 static SIGHANDLER_T old_sigalrm_handler = SIG_ERR;
 149 static SIGHANDLER_T old_sigint_handler  = SIG_ERR;
 150 static SIGHANDLER_T old_sigterm_handler = SIG_ERR;
 151
 152 /* var which if set indicates that the program should finish execution */
 153
 154 SIG_ATOMIC_T got_exit_signal = 0;
 155
 156 /* if next is set indicates the first signal handled in exit_signal_handler */
 157
 158 static volatile int exit_signal = 0;
 159
 160 /* signal handler that will be triggered to indicate that the program
 161   should finish its execution in a controlled manner as soon as possible.
 162   The first time this is called it will set got_exit_signal to one and
 163   store in exit_signal the signal that triggered its execution. */
 164
 165 static RETSIGTYPE exit_signal_handler(int signum)
 166 {
 167   int old_errno = ERRNO;
 168   if(got_exit_signal == 0) {
 169     got_exit_signal = 1;
 170     exit_signal = signum;
 171   }
 172   (void)signal(signum, exit_signal_handler);
 173   SET_ERRNO(old_errno);
 174 }
 175
 176 static void install_signal_handlers(void)
 177 {
 178 #ifdef SIGHUP
 179   /* ignore SIGHUP signal */
 180   if((old_sighup_handler = signal(SIGHUP, SIG_IGN)) == SIG_ERR)
 181     logmsg("cannot install SIGHUP handler: 5s", strerror(ERRNO));
 182 #endif
 183 #ifdef SIGPIPE
 184   /* ignore SIGPIPE signal */
 185   if((old_sigpipe_handler = signal(SIGPIPE, SIG_IGN)) == SIG_ERR)
 186     logmsg("cannot install SIGPIPE handler: 5s", strerror(ERRNO));
 187 #endif
 188 #ifdef SIGALRM
 189   /* ignore SIGALRM signal */
 190   if((old_sigalrm_handler = signal(SIGALRM, SIG_IGN)) == SIG_ERR)
 191     logmsg("cannot install SIGALRM handler: 5s", strerror(ERRNO));
 192 #endif
 193 #ifdef SIGINT
 194   /* handle SIGINT signal with our exit_signal_handler */
 195   if((old_sigint_handler = signal(SIGINT, exit_signal_handler)) == SIG_ERR)
 196     logmsg("cannot install SIGINT handler: 5s", strerror(ERRNO));
 197   else
 198     siginterrupt(SIGINT, 1);
 199 #endif
 200 #ifdef SIGTERM
 201   /* handle SIGTERM signal with our exit_signal_handler */
 202   if((old_sigterm_handler = signal(SIGTERM, exit_signal_handler)) == SIG_ERR)
 203     logmsg("cannot install SIGTERM handler: 5s", strerror(ERRNO));
 204   else
 205     siginterrupt(SIGTERM, 1);
 206 #endif
 207 }
 208
 209 static void restore_signal_handlers(void)
 210 {
 211 #ifdef SIGHUP
 212   if(SIG_ERR != old_sighup_handler)
 213     (void)signal(SIGHUP, old_sighup_handler);
 214 #endif
 215 #ifdef SIGPIPE
 216   if(SIG_ERR != old_sigpipe_handler)
 217     (void)signal(SIGPIPE, old_sigpipe_handler);
 218 #endif
 219 #ifdef SIGALRM
 220   if(SIG_ERR != old_sigalrm_handler)
 221     (void)signal(SIGALRM, old_sigalrm_handler);
 222 #endif
 223 #ifdef SIGINT
 224   if(SIG_ERR != old_sigint_handler)
 225     (void)signal(SIGINT, old_sigint_handler);
 226 #endif
 227 #ifdef SIGTERM
 228   if(SIG_ERR != old_sigterm_handler)
 229     (void)signal(SIGTERM, old_sigterm_handler);
 230 #endif
 231 }
 232
 233 /*
 234  * fullread is a wrapper around the read() function. This will repeat the call
 235  * to read() until it actually has read the complete number of bytes indicated
 236  * in nbytes or it fails with a condition that cannot be handled with a simple
 237  * retry of the read call.
 238  */
 239
 240 static ssize_t fullread(int filedes, void *buffer, size_t nbytes)
 241 {
 242   int error;
 243   ssize_t rc;
 244   ssize_t nread = 0;
 245
 246   do {
 247     rc = read(filedes, (unsigned char *)buffer + nread, nbytes - nread);
 248
 249     if(got_exit_signal) {
 250       logmsg("signalled to die");
 251       return -1;
 252     }
 253
 254     if(rc < 0) {
 255       error = ERRNO;
 256       if((error == EINTR) || (error == EAGAIN))
 257         continue;
 258       logmsg("unrecoverable read() failure: %s", strerror(error));
 259       return -1;
 260     }
 261
 262     if(rc == 0) {
 263       logmsg("got 0 reading from stdin");
 264       return 0;
 265     }
 266
 267     nread += rc;
 268
 269   } while((size_t)nread < nbytes);
 270
 271   if(verbose)
 272     logmsg("read %ld bytes", (long)nread);
 273
 274   return nread;
 275 }
 276
 277 /*
 278  * fullwrite is a wrapper around the write() function. This will repeat the
 279  * call to write() until it actually has written the complete number of bytes
 280  * indicated in nbytes or it fails with a condition that cannot be handled
 281  * with a simple retry of the write call.
 282  */
 283
 284 static ssize_t fullwrite(int filedes, const void *buffer, size_t nbytes)
 285 {
 286   int error;
 287   ssize_t wc;
 288   ssize_t nwrite = 0;
 289
 290   do {
 291     wc = write(filedes, (unsigned char *)buffer + nwrite, nbytes - nwrite);
 292
 293     if(got_exit_signal) {
 294       logmsg("signalled to die");
 295       return -1;
 296     }
 297
 298     if(wc < 0) {
 299       error = ERRNO;
 300       if((error == EINTR) || (error == EAGAIN))
 301         continue;
 302       logmsg("unrecoverable write() failure: %s", strerror(error));
 303       return -1;
 304     }
 305
 306     if(wc == 0) {
 307       logmsg("put 0 writing to stdout");
 308       return 0;
 309     }
 310
 311     nwrite += wc;
 312
 313   } while((size_t)nwrite < nbytes);
 314
 315   if(verbose)
 316     logmsg("wrote %ld bytes", (long)nwrite);
 317
 318   return nwrite;
 319 }
 320
 321 /*
 322  * read_stdin tries to read from stdin nbytes into the given buffer. This is a
 323  * blocking function that will only return TRUE when nbytes have actually been
 324  * read or FALSE when an unrecoverable error has been detected. Failure of this
 325  * function is an indication that the sockfilt process should terminate.
 326  */
 327
 328 static bool read_stdin(void *buffer, size_t nbytes)
 329 {
 330   ssize_t nread = fullread(fileno(stdin), buffer, nbytes);
 331   if(nread != (ssize_t)nbytes) {
 332     logmsg("exiting...");
 333     return FALSE;
 334   }
 335   return TRUE;
 336 }
 337
 338 /*
 339  * write_stdout tries to write to stdio nbytes from the given buffer. This is a
 340  * blocking function that will only return TRUE when nbytes have actually been
 341  * written or FALSE when an unrecoverable error has been detected. Failure of
 342  * this function is an indication that the sockfilt process should terminate.
 343  */
 344
 345 static bool write_stdout(const void *buffer, size_t nbytes)
 346 {
 347   ssize_t nwrite = fullwrite(fileno(stdout), buffer, nbytes);
 348   if(nwrite != (ssize_t)nbytes) {
 349     logmsg("exiting...");
 350     return FALSE;
 351   }
 352   return TRUE;
 353 }
 354
 355 static void lograw(unsigned char *buffer, ssize_t len)
 356 {
 357   char data[120];
 358   ssize_t i;
 359   unsigned char *ptr = buffer;
 360   char *optr = data;
 361   ssize_t width=0;
 362
 363   for(i=0; i<len; i++) {
 364     switch(ptr[i]) {
 365     case '\n':
 366       sprintf(optr, "\\n");
 367       width += 2;
 368       optr += 2;
 369       break;
 370     case '\r':
 371       sprintf(optr, "\\r");
 372       width += 2;
 373       optr += 2;
 374       break;
 375     default:
 376       sprintf(optr, "%c", (ISGRAPH(ptr[i]) || ptr[i]==0x20) ?ptr[i]:'.');
 377       width++;
 378       optr++;
 379       break;
 380     }
 381
 382     if(width>60) {
 383       logmsg("'%s'", data);
 384       width = 0;
 385       optr = data;
 386     }
 387   }
 388   if(width)
 389     logmsg("'%s'", data);
 390 }
 391
 392 /*
 393   sockfdp is a pointer to an established stream or CURL_SOCKET_BAD
 394
 395   if sockfd is CURL_SOCKET_BAD, listendfd is a listening socket we must
 396   accept()
 397 */
 398 static bool juggle(curl_socket_t *sockfdp,
 399                    curl_socket_t listenfd,
 400                    enum sockmode *mode)
 401 {
 402   struct timeval timeout;
 403   fd_set fds_read;
 404   fd_set fds_write;
 405   fd_set fds_err;
 406   curl_socket_t sockfd;
 407   curl_socket_t maxfd;
 408   ssize_t rc;
 409   ssize_t nread_socket;
 410   ssize_t bytes_written;
 411   ssize_t buffer_len;
 412   int error;
 413
 414  /* 'buffer' is this excessively large only to be able to support things like
 415     test 1003 which tests exceedingly large server response lines */
 416   unsigned char buffer[17010];
 417   char data[16];
 418
 419   if(got_exit_signal) {
 420     logmsg("signalled to die, exiting...");
 421     return FALSE;
 422   }
 423
 424 #ifdef HAVE_GETPPID
 425   /* As a last resort, quit if sockfilt process becomes orphan. Just in case
 426      parent ftpserver process has died without killing its sockfilt children */
 427   if(getppid() <= 1) {
 428     logmsg("process becomes orphan, exiting");
 429     return FALSE;
 430   }
 431 #endif
 432
 433   timeout.tv_sec = 120;
 434   timeout.tv_usec = 0;
 435
 436   FD_ZERO(&fds_read);
 437   FD_ZERO(&fds_write);
 438   FD_ZERO(&fds_err);
 439
 440   FD_SET(fileno(stdin), &fds_read);
 441
 442   switch(*mode) {
 443
 444   case PASSIVE_LISTEN:
 445
 446     /* server mode */
 447     sockfd = listenfd;
 448     /* there's always a socket to wait for */
 449     FD_SET(sockfd, &fds_read);
 450     maxfd = sockfd;
 451     break;
 452
 453   case PASSIVE_CONNECT:
 454
 455     sockfd = *sockfdp;
 456     if(CURL_SOCKET_BAD == sockfd) {
 457       /* eeek, we are supposedly connected and then this cannot be -1 ! */
 458       logmsg("socket is -1! on %s:%d", __FILE__, __LINE__);
 459       maxfd = 0; /* stdin */
 460     }
 461     else {
 462       /* there's always a socket to wait for */
 463       FD_SET(sockfd, &fds_read);
 464       maxfd = sockfd;
 465     }
 466     break;
 467
 468   case ACTIVE:
 469
 470     sockfd = *sockfdp;
 471     /* sockfd turns CURL_SOCKET_BAD when our connection has been closed */
 472     if(CURL_SOCKET_BAD != sockfd) {
 473       FD_SET(sockfd, &fds_read);
 474       maxfd = sockfd;
 475     }
 476     else {
 477       logmsg("No socket to read on");
 478       maxfd = 0;
 479     }
 480     break;
 481
 482   case ACTIVE_DISCONNECT:
 483
 484     logmsg("disconnected, no socket to read on");
 485     maxfd = 0;
 486     sockfd = CURL_SOCKET_BAD;
 487     break;
 488
 489   } /* switch(*mode) */
 490
 491
 492   do {
 493
 494     rc = select((int)maxfd + 1, &fds_read, &fds_write, &fds_err, &timeout);
 495
 496     if(got_exit_signal) {
 497       logmsg("signalled to die, exiting...");
 498       return FALSE;
 499     }
 500
 501   } while((rc == -1) && ((error = SOCKERRNO) == EINTR));
 502
 503   if(rc < 0) {
 504     logmsg("select() failed with error: (%d) %s",
 505            error, strerror(error));
 506     return FALSE;
 507   }
 508
 509   if(rc == 0)
 510     /* timeout */
 511     return TRUE;
 512
 513
 514   if(FD_ISSET(fileno(stdin), &fds_read)) {
 515     /* read from stdin, commands/data to be dealt with and possibly passed on
 516        to the socket
 517
 518        protocol:
 519
 520        4 letter command + LF [mandatory]
 521
 522        4-digit hexadecimal data length + LF [if the command takes data]
 523        data                       [the data being as long as set above]
 524
 525        Commands:
 526
 527        DATA - plain pass-thru data
 528     */
 529
 530     if(!read_stdin(buffer, 5))
 531       return FALSE;
 532
 533     logmsg("Received %c%c%c%c (on stdin)",
 534            buffer[0], buffer[1], buffer[2], buffer[3] );
 535
 536     if(!memcmp("PING", buffer, 4)) {
 537       /* send reply on stdout, just proving we are alive */
 538       if(!write_stdout("PONG\n", 5))
 539         return FALSE;
 540     }
 541
 542     else if(!memcmp("PORT", buffer, 4)) {
 543       /* Question asking us what PORT number we are listening to.
 544          Replies to PORT with "IPv[num]/[port]" */
 545       sprintf((char *)buffer, "IPv%d/%d\n", use_ipv6?6:4, (int)port);
 546       buffer_len = (ssize_t)strlen((char *)buffer);
 547       snprintf(data, sizeof(data), "PORT\n%04x\n", buffer_len);
 548       if(!write_stdout(data, 10))
 549         return FALSE;
 550       if(!write_stdout(buffer, buffer_len))
 551         return FALSE;
 552     }
 553     else if(!memcmp("QUIT", buffer, 4)) {
 554       /* just die */
 555       logmsg("quits");
 556       return FALSE;
 557     }
 558     else if(!memcmp("DATA", buffer, 4)) {
 559       /* data IN => data OUT */
 560
 561       if(!read_stdin(buffer, 5))
 562         return FALSE;
 563
 564       buffer[5] = '\0';
 565
 566       buffer_len = (ssize_t)strtol((char *)buffer, NULL, 16);
 567       if (buffer_len > (ssize_t)sizeof(buffer)) {
 568         logmsg("ERROR: Buffer size (%ld bytes) too small for data size "
 569                "(%ld bytes)", (long)sizeof(buffer), (long)buffer_len);
 570         return FALSE;
 571       }
 572       logmsg("> %d bytes data, server => client", buffer_len);
 573
 574       if(!read_stdin(buffer, buffer_len))
 575         return FALSE;
 576
 577       lograw(buffer, buffer_len);
 578
 579       if(*mode == PASSIVE_LISTEN) {
 580         logmsg("*** We are disconnected!");
 581         if(!write_stdout("DISC\n", 5))
 582           return FALSE;
 583       }
 584       else {
 585         /* send away on the socket */
 586         bytes_written = swrite(sockfd, buffer, buffer_len);
 587         if(bytes_written != buffer_len) {
 588           logmsg("Not all data was sent. Bytes to send: %d sent: %d",
 589                  buffer_len, bytes_written);
 590         }
 591       }
 592     }
 593     else if(!memcmp("DISC", buffer, 4)) {
 594       /* disconnect! */
 595       if(!write_stdout("DISC\n", 5))
 596         return FALSE;
 597       if(sockfd != CURL_SOCKET_BAD) {
 598         logmsg("====> Client forcibly disconnected");
 599         sclose(sockfd);
 600         *sockfdp = CURL_SOCKET_BAD;
 601         if(*mode == PASSIVE_CONNECT)
 602           *mode = PASSIVE_LISTEN;
 603         else
 604           *mode = ACTIVE_DISCONNECT;
 605       }
 606       else
 607         logmsg("attempt to close already dead connection");
 608       return TRUE;
 609     }
 610   }
 611
 612
 613   if((sockfd != CURL_SOCKET_BAD) && (FD_ISSET(sockfd, &fds_read)) ) {
 614
 615     if(*mode == PASSIVE_LISTEN) {
 616       /* there's no stream set up yet, this is an indication that there's a
 617          client connecting. */
 618       sockfd = accept(sockfd, NULL, NULL);
 619       if(CURL_SOCKET_BAD == sockfd)
 620         logmsg("accept() failed");
 621       else {
 622         logmsg("====> Client connect");
 623         if(!write_stdout("CNCT\n", 5))
 624           return FALSE;
 625         *sockfdp = sockfd; /* store the new socket */
 626         *mode = PASSIVE_CONNECT; /* we have connected */
 627       }
 628       return TRUE;
 629     }
 630
 631     /* read from socket, pass on data to stdout */
 632     nread_socket = sread(sockfd, buffer, sizeof(buffer));
 633
 634     if(nread_socket <= 0) {
 635       logmsg("====> Client disconnect");
 636       if(!write_stdout("DISC\n", 5))
 637         return FALSE;
 638       sclose(sockfd);
 639       *sockfdp = CURL_SOCKET_BAD;
 640       if(*mode == PASSIVE_CONNECT)
 641         *mode = PASSIVE_LISTEN;
 642       else
 643         *mode = ACTIVE_DISCONNECT;
 644       return TRUE;
 645     }
 646
 647     snprintf(data, sizeof(data), "DATA\n%04x\n", nread_socket);
 648     if(!write_stdout(data, 10))
 649       return FALSE;
 650     if(!write_stdout(buffer, nread_socket))
 651       return FALSE;
 652
 653     logmsg("< %d bytes data, client => server", nread_socket);
 654     lograw(buffer, nread_socket);
 655   }
 656
 657   return TRUE;
 658 }
 659
 660 static curl_socket_t sockdaemon(curl_socket_t sock,
 661                                 unsigned short *listenport)
 662 {
 663   /* passive daemon style */
 664   struct sockaddr_in me;
 665 #ifdef ENABLE_IPV6
 666   struct sockaddr_in6 me6;
 667 #endif /* ENABLE_IPV6 */
 668   int flag = 1;
 669   int rc;
 670   int totdelay = 0;
 671   int maxretr = 10;
 672   int delay= 20;
 673   int attempt = 0;
 674   int error = 0;
 675
 676   do {
 677     attempt++;
 678     rc = setsockopt(sock, SOL_SOCKET, SO_REUSEADDR,
 679          (void *)&flag, sizeof(flag));
 680     if(rc) {
 681       error = SOCKERRNO;
 682       if(maxretr) {
 683         rc = wait_ms(delay);
 684         if(rc) {
 685           /* should not happen */
 686           error = SOCKERRNO;
 687           logmsg("wait_ms() failed: (%d) %s", error, strerror(error));
 688           sclose(sock);
 689           return CURL_SOCKET_BAD;
 690         }
 691         if(got_exit_signal) {
 692           logmsg("signalled to die, exiting...");
 693           sclose(sock);
 694           return CURL_SOCKET_BAD;
 695         }
 696         totdelay += delay;
 697         delay *= 2; /* double the sleep for next attempt */
 698       }
 699     }
 700   } while(rc && maxretr--);
 701
 702   if(rc) {
 703     logmsg("setsockopt(SO_REUSEADDR) failed %d times in %d ms. Error: (%d) %s",
 704            attempt, totdelay, error, strerror(error));
 705     logmsg("Continuing anyway...");
 706   }
 707
 708 #ifdef ENABLE_IPV6
 709   if(!use_ipv6) {
 710 #endif
 711     memset(&me, 0, sizeof(me));
 712     me.sin_family = AF_INET;
 713     me.sin_addr.s_addr = INADDR_ANY;
 714     me.sin_port = htons(*listenport);
 715     rc = bind(sock, (struct sockaddr *) &me, sizeof(me));
 716 #ifdef ENABLE_IPV6
 717   }
 718   else {
 719     memset(&me6, 0, sizeof(me6));
 720     me6.sin6_family = AF_INET6;
 721     me6.sin6_addr = in6addr_any;
 722     me6.sin6_port = htons(*listenport);
 723     rc = bind(sock, (struct sockaddr *) &me6, sizeof(me6));
 724   }
 725 #endif /* ENABLE_IPV6 */
 726   if(rc) {
 727     error = SOCKERRNO;
 728     logmsg("Error binding socket: (%d) %s", error, strerror(error));
 729     sclose(sock);
 730     return CURL_SOCKET_BAD;
 731   }
 732
 733   if(!*listenport) {
 734     /* The system picked a port number, now figure out which port we actually
 735        got */
 736     /* we succeeded to bind */
 737     struct sockaddr_in add;
 738     socklen_t socksize = sizeof(add);
 739
 740     if(getsockname(sock, (struct sockaddr *) &add,
 741                    &socksize)<0) {
 742       error = SOCKERRNO;
 743       logmsg("getsockname() failed with error: (%d) %s",
 744              error, strerror(error));
 745       sclose(sock);
 746       return CURL_SOCKET_BAD;
 747     }
 748     *listenport = ntohs(add.sin_port);
 749   }
 750
 751   /* start accepting connections */
 752   rc = listen(sock, 5);
 753   if(0 != rc) {
 754     error = SOCKERRNO;
 755     logmsg("listen() failed with error: (%d) %s",
 756            error, strerror(error));
 757     sclose(sock);
 758     return CURL_SOCKET_BAD;
 759   }
 760
 761   return sock;
 762 }
 763
 764
 765 int main(int argc, char *argv[])
 766 {
 767   struct sockaddr_in me;
 768 #ifdef ENABLE_IPV6
 769   struct sockaddr_in6 me6;
 770 #endif /* ENABLE_IPV6 */
 771   curl_socket_t sock = CURL_SOCKET_BAD;
 772   curl_socket_t msgsock = CURL_SOCKET_BAD;
 773   int wrotepidfile = 0;
 774   char *pidname= (char *)".sockfilt.pid";
 775   int rc;
 776   int error;
 777   int arg=1;
 778   enum sockmode mode = PASSIVE_LISTEN; /* default */
 779   const char *addr = NULL;
 780
 781   while(argc>arg) {
 782     if(!strcmp("--version", argv[arg])) {
 783       printf("sockfilt IPv4%s\n",
 784 #ifdef ENABLE_IPV6
 785              "/IPv6"
 786 #else
 787              ""
 788 #endif
 789              );
 790       return 0;
 791     }
 792     else if(!strcmp("--verbose", argv[arg])) {
 793       verbose = TRUE;
 794       arg++;
 795     }
 796     else if(!strcmp("--pidfile", argv[arg])) {
 797       arg++;
 798       if(argc>arg)
 799         pidname = argv[arg++];
 800     }
 801     else if(!strcmp("--logfile", argv[arg])) {
 802       arg++;
 803       if(argc>arg)
 804         serverlogfile = argv[arg++];
 805     }
 806     else if(!strcmp("--ipv6", argv[arg])) {
 807 #ifdef ENABLE_IPV6
 808       use_ipv6=TRUE;
 809 #endif
 810       arg++;
 811     }
 812     else if(!strcmp("--ipv4", argv[arg])) {
 813       /* for completeness, we support this option as well */
 814       use_ipv6=FALSE;
 815       arg++;
 816     }
 817     else if(!strcmp("--port", argv[arg])) {
 818       arg++;
 819       if(argc>arg) {
 820         port = (unsigned short)atoi(argv[arg]);
 821         arg++;
 822       }
 823     }
 824     else if(!strcmp("--connect", argv[arg])) {
 825       /* Asked to actively connect to the specified local port instead of
 826          doing a passive server-style listening. */
 827       arg++;
 828       if(argc>arg) {
 829         connectport = (unsigned short)atoi(argv[arg]);
 830         arg++;
 831       }
 832     }
 833     else if(!strcmp("--addr", argv[arg])) {
 834       /* Set an IP address to use with --connect; otherwise use localhost */
 835       arg++;
 836       if(argc>arg) {
 837         addr = argv[arg];
 838         arg++;
 839       }
 840     }
 841     else {
 842       puts("Usage: sockfilt [option]\n"
 843            " --version\n"
 844            " --verbose\n"
 845            " --logfile [file]\n"
 846            " --pidfile [file]\n"
 847            " --ipv4\n"
 848            " --ipv6\n"
 849            " --port [port]\n"
 850            " --connect [port]\n"
 851            " --addr [address]");
 852       return 0;
 853     }
 854   }
 855
 856 #ifdef WIN32
 857   win32_init();
 858   atexit(win32_cleanup);
 859 #endif
 860
 861   install_signal_handlers();
 862
 863 #ifdef ENABLE_IPV6
 864   if(!use_ipv6)
 865 #endif
 866     sock = socket(AF_INET, SOCK_STREAM, 0);
 867 #ifdef ENABLE_IPV6
 868   else
 869     sock = socket(AF_INET6, SOCK_STREAM, 0);
 870 #endif
 871
 872   if(CURL_SOCKET_BAD == sock) {
 873     error = SOCKERRNO;
 874     logmsg("Error creating socket: (%d) %s",
 875            error, strerror(error));
 876     goto sockfilt_cleanup;
 877   }
 878
 879   if(connectport) {
 880     /* Active mode, we should connect to the given port number */
 881     mode = ACTIVE;
 882 #ifdef ENABLE_IPV6
 883     if(!use_ipv6) {
 884 #endif
 885       memset(&me, 0, sizeof(me));
 886       me.sin_family = AF_INET;
 887       me.sin_port = htons(connectport);
 888       me.sin_addr.s_addr = INADDR_ANY;
 889       if (!addr)
 890         addr = "127.0.0.1";
 891       Curl_inet_pton(AF_INET, addr, &me.sin_addr);
 892
 893       rc = connect(sock, (struct sockaddr *) &me, sizeof(me));
 894 #ifdef ENABLE_IPV6
 895     }
 896     else {
 897       memset(&me6, 0, sizeof(me6));
 898       me6.sin6_family = AF_INET6;
 899       me6.sin6_port = htons(connectport);
 900       if (!addr)
 901         addr = "::1";
 902       Curl_inet_pton(AF_INET6, addr, &me6.sin6_addr);
 903
 904       rc = connect(sock, (struct sockaddr *) &me6, sizeof(me6));
 905     }
 906 #endif /* ENABLE_IPV6 */
 907     if(rc) {
 908       error = SOCKERRNO;
 909       logmsg("Error connecting to port %d: (%d) %s",
 910              connectport, error, strerror(error));
 911       goto sockfilt_cleanup;
 912     }
 913     logmsg("====> Client connect");
 914     msgsock = sock; /* use this as stream */
 915   }
 916   else {
 917     /* passive daemon style */
 918     sock = sockdaemon(sock, &port);
 919     if(CURL_SOCKET_BAD == sock)
 920       goto sockfilt_cleanup;
 921     msgsock = CURL_SOCKET_BAD; /* no stream socket yet */
 922   }
 923
 924   logmsg("Running IPv%d version",
 925          (use_ipv6?6:4));
 926
 927   if(connectport)
 928     logmsg("Connected to port %d", connectport);
 929   else
 930     logmsg("Listening on port %d", port);
 931
 932   wrotepidfile = write_pidfile(pidname);
 933   if(!wrotepidfile)
 934     goto sockfilt_cleanup;
 935
 936   while(juggle(&msgsock, sock, &mode));
 937
 938 sockfilt_cleanup:
 939
 940   if((msgsock != sock) && (msgsock != CURL_SOCKET_BAD))
 941     sclose(msgsock);
 942
 943   if(sock != CURL_SOCKET_BAD)
 944     sclose(sock);
 945
 946   if(wrotepidfile)
 947     unlink(pidname);
 948
 949   restore_signal_handlers();
 950
 951   if(got_exit_signal) {
 952     logmsg("============> sockfilt exits with signal (%d)", exit_signal);
 953     /*
 954      * To properly set the return status of the process we
 955      * must raise the same signal SIGINT or SIGTERM that we
 956      * caught and let the old handler take care of it.
 957      */
 958     raise(exit_signal);
 959   }
 960
 961   logmsg("============> sockfilt quits");
 962   return 0;
 963 }
 964