1/*************************************************************************** 2 * _ _ ____ _ 3 * Project ___| | | | _ \| | 4 * / __| | | | |_) | | 5 * | (__| |_| | _ <| |___ 6 * \___|\___/|_| \_\_____| 7 * 8 * Copyright (C) 1998 - 2010, 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 ***************************************************************************/ 22 23/* Purpose 24 * 25 * 1. Accept a TCP connection on a custom port (ipv4 or ipv6), or connect 26 * to a given (localhost) port. 27 * 28 * 2. Get commands on STDIN. Pass data on to the TCP stream. 29 * Get data from TCP stream and pass on to STDOUT. 30 * 31 * This program is made to perform all the socket/stream/connection stuff for 32 * the test suite's (perl) FTP server. Previously the perl code did all of 33 * this by its own, but I decided to let this program do the socket layer 34 * because of several things: 35 * 36 * o We want the perl code to work with rather old perl installations, thus 37 * we cannot use recent perl modules or features. 38 * 39 * o We want IPv6 support for systems that provide it, and doing optional IPv6 40 * support in perl seems if not impossible so at least awkward. 41 * 42 * o We want FTP-SSL support, which means that a connection that starts with 43 * plain sockets needs to be able to "go SSL" in the midst. This would also 44 * require some nasty perl stuff I'd rather avoid. 45 * 46 * (Source originally based on sws.c) 47 */ 48 49/* 50 * Signal handling notes for sockfilt 51 * ---------------------------------- 52 * 53 * This program is a single-threaded process. 54 * 55 * This program is intended to be highly portable and as such it must be kept as 56 * simple as possible, due to this the only signal handling mechanisms used will 57 * be those of ANSI C, and used only in the most basic form which is good enough 58 * for the purpose of this program. 59 * 60 * For the above reason and the specific needs of this program signals SIGHUP, 61 * SIGPIPE and SIGALRM will be simply ignored on systems where this can be done. 62 * If possible, signals SIGINT and SIGTERM will be handled by this program as an 63 * indication to cleanup and finish execution as soon as possible. This will be 64 * achieved with a single signal handler 'exit_signal_handler' for both signals. 65 * 66 * The 'exit_signal_handler' upon the first SIGINT or SIGTERM received signal 67 * will just set to one the global var 'got_exit_signal' storing in global var 68 * 'exit_signal' the signal that triggered this change. 69 * 70 * Nothing fancy that could introduce problems is used, the program at certain 71 * points in its normal flow checks if var 'got_exit_signal' is set and in case 72 * this is true it just makes its way out of loops and functions in structured 73 * and well behaved manner to achieve proper program cleanup and termination. 74 * 75 * Even with the above mechanism implemented it is worthwile to note that other 76 * signals might still be received, or that there might be systems on which it 77 * is not possible to trap and ignore some of the above signals. This implies 78 * that for increased portability and reliability the program must be coded as 79 * if no signal was being ignored or handled at all. Enjoy it! 80 */ 81 82#define CURL_NO_OLDIES 83 84#include "setup.h" /* portability help from the lib directory */ 85 86#ifdef HAVE_SIGNAL_H 87#include <signal.h> 88#endif 89#ifdef HAVE_UNISTD_H 90#include <unistd.h> 91#endif 92#ifdef HAVE_SYS_SOCKET_H 93#include <sys/socket.h> 94#endif 95#ifdef HAVE_NETINET_IN_H 96#include <netinet/in.h> 97#endif 98#ifdef HAVE_ARPA_INET_H 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#include "server_sockaddr.h" 113 114/* include memdebug.h last */ 115#include "memdebug.h" 116 117#define DEFAULT_PORT 8999 118 119#ifndef DEFAULT_LOGFILE 120#define DEFAULT_LOGFILE "log/sockfilt.log" 121#endif 122 123const char *serverlogfile = DEFAULT_LOGFILE; 124 125static bool verbose = FALSE; 126#ifdef ENABLE_IPV6 127static bool use_ipv6 = FALSE; 128#endif 129static const char *ipv_inuse = "IPv4"; 130static unsigned short port = DEFAULT_PORT; 131static unsigned short connectport = 0; /* if non-zero, we activate this mode */ 132 133enum sockmode { 134 PASSIVE_LISTEN, /* as a server waiting for connections */ 135 PASSIVE_CONNECT, /* as a server, connected to a client */ 136 ACTIVE, /* as a client, connected to a server */ 137 ACTIVE_DISCONNECT /* as a client, disconnected from server */ 138}; 139 140/* do-nothing macro replacement for systems which lack siginterrupt() */ 141 142#ifndef HAVE_SIGINTERRUPT 143#define siginterrupt(x,y) do {} while(0) 144#endif 145 146/* vars used to keep around previous signal handlers */ 147 148typedef RETSIGTYPE (*SIGHANDLER_T)(int); 149 150#ifdef SIGHUP 151static SIGHANDLER_T old_sighup_handler = SIG_ERR; 152#endif 153 154#ifdef SIGPIPE 155static SIGHANDLER_T old_sigpipe_handler = SIG_ERR; 156#endif 157 158#ifdef SIGALRM 159static SIGHANDLER_T old_sigalrm_handler = SIG_ERR; 160#endif 161 162#ifdef SIGINT 163static SIGHANDLER_T old_sigint_handler = SIG_ERR; 164#endif 165 166#ifdef SIGTERM 167static SIGHANDLER_T old_sigterm_handler = SIG_ERR; 168#endif 169 170/* var which if set indicates that the program should finish execution */ 171 172SIG_ATOMIC_T got_exit_signal = 0; 173 174/* if next is set indicates the first signal handled in exit_signal_handler */ 175 176static volatile int exit_signal = 0; 177 178/* signal handler that will be triggered to indicate that the program 179 should finish its execution in a controlled manner as soon as possible. 180 The first time this is called it will set got_exit_signal to one and 181 store in exit_signal the signal that triggered its execution. */ 182 183static RETSIGTYPE exit_signal_handler(int signum) 184{ 185 int old_errno = ERRNO; 186 if(got_exit_signal == 0) { 187 got_exit_signal = 1; 188 exit_signal = signum; 189 } 190 (void)signal(signum, exit_signal_handler); 191 SET_ERRNO(old_errno); 192} 193 194static void install_signal_handlers(void) 195{ 196#ifdef SIGHUP 197 /* ignore SIGHUP signal */ 198 if((old_sighup_handler = signal(SIGHUP, SIG_IGN)) == SIG_ERR) 199 logmsg("cannot install SIGHUP handler: %s", strerror(ERRNO)); 200#endif 201#ifdef SIGPIPE 202 /* ignore SIGPIPE signal */ 203 if((old_sigpipe_handler = signal(SIGPIPE, SIG_IGN)) == SIG_ERR) 204 logmsg("cannot install SIGPIPE handler: %s", strerror(ERRNO)); 205#endif 206#ifdef SIGALRM 207 /* ignore SIGALRM signal */ 208 if((old_sigalrm_handler = signal(SIGALRM, SIG_IGN)) == SIG_ERR) 209 logmsg("cannot install SIGALRM handler: %s", strerror(ERRNO)); 210#endif 211#ifdef SIGINT 212 /* handle SIGINT signal with our exit_signal_handler */ 213 if((old_sigint_handler = signal(SIGINT, exit_signal_handler)) == SIG_ERR) 214 logmsg("cannot install SIGINT handler: %s", strerror(ERRNO)); 215 else 216 siginterrupt(SIGINT, 1); 217#endif 218#ifdef SIGTERM 219 /* handle SIGTERM signal with our exit_signal_handler */ 220 if((old_sigterm_handler = signal(SIGTERM, exit_signal_handler)) == SIG_ERR) 221 logmsg("cannot install SIGTERM handler: %s", strerror(ERRNO)); 222 else 223 siginterrupt(SIGTERM, 1); 224#endif 225} 226 227static void restore_signal_handlers(void) 228{ 229#ifdef SIGHUP 230 if(SIG_ERR != old_sighup_handler) 231 (void)signal(SIGHUP, old_sighup_handler); 232#endif 233#ifdef SIGPIPE 234 if(SIG_ERR != old_sigpipe_handler) 235 (void)signal(SIGPIPE, old_sigpipe_handler); 236#endif 237#ifdef SIGALRM 238 if(SIG_ERR != old_sigalrm_handler) 239 (void)signal(SIGALRM, old_sigalrm_handler); 240#endif 241#ifdef SIGINT 242 if(SIG_ERR != old_sigint_handler) 243 (void)signal(SIGINT, old_sigint_handler); 244#endif 245#ifdef SIGTERM 246 if(SIG_ERR != old_sigterm_handler) 247 (void)signal(SIGTERM, old_sigterm_handler); 248#endif 249} 250 251/* 252 * fullread is a wrapper around the read() function. This will repeat the call 253 * to read() until it actually has read the complete number of bytes indicated 254 * in nbytes or it fails with a condition that cannot be handled with a simple 255 * retry of the read call. 256 */ 257 258static ssize_t fullread(int filedes, void *buffer, size_t nbytes) 259{ 260 int error; 261 ssize_t rc; 262 ssize_t nread = 0; 263 264 do { 265 rc = read(filedes, (unsigned char *)buffer + nread, nbytes - nread); 266 267 if(got_exit_signal) { 268 logmsg("signalled to die"); 269 return -1; 270 } 271 272 if(rc < 0) { 273 error = ERRNO; 274 if((error == EINTR) || (error == EAGAIN)) 275 continue; 276 logmsg("unrecoverable read() failure: %s", strerror(error)); 277 return -1; 278 } 279 280 if(rc == 0) { 281 logmsg("got 0 reading from stdin"); 282 return 0; 283 } 284 285 nread += rc; 286 287 } while((size_t)nread < nbytes); 288 289 if(verbose) 290 logmsg("read %zd bytes", nread); 291 292 return nread; 293} 294 295/* 296 * fullwrite is a wrapper around the write() function. This will repeat the 297 * call to write() until it actually has written the complete number of bytes 298 * indicated in nbytes or it fails with a condition that cannot be handled 299 * with a simple retry of the write call. 300 */ 301 302static ssize_t fullwrite(int filedes, const void *buffer, size_t nbytes) 303{ 304 int error; 305 ssize_t wc; 306 ssize_t nwrite = 0; 307 308 do { 309 wc = write(filedes, (unsigned char *)buffer + nwrite, nbytes - nwrite); 310 311 if(got_exit_signal) { 312 logmsg("signalled to die"); 313 return -1; 314 } 315 316 if(wc < 0) { 317 error = ERRNO; 318 if((error == EINTR) || (error == EAGAIN)) 319 continue; 320 logmsg("unrecoverable write() failure: %s", strerror(error)); 321 return -1; 322 } 323 324 if(wc == 0) { 325 logmsg("put 0 writing to stdout"); 326 return 0; 327 } 328 329 nwrite += wc; 330 331 } while((size_t)nwrite < nbytes); 332 333 if(verbose) 334 logmsg("wrote %zd bytes", nwrite); 335 336 return nwrite; 337} 338 339/* 340 * read_stdin tries to read from stdin nbytes into the given buffer. This is a 341 * blocking function that will only return TRUE when nbytes have actually been 342 * read or FALSE when an unrecoverable error has been detected. Failure of this 343 * function is an indication that the sockfilt process should terminate. 344 */ 345 346static bool read_stdin(void *buffer, size_t nbytes) 347{ 348 ssize_t nread = fullread(fileno(stdin), buffer, nbytes); 349 if(nread != (ssize_t)nbytes) { 350 logmsg("exiting..."); 351 return FALSE; 352 } 353 return TRUE; 354} 355 356/* 357 * write_stdout tries to write to stdio nbytes from the given buffer. This is a 358 * blocking function that will only return TRUE when nbytes have actually been 359 * written or FALSE when an unrecoverable error has been detected. Failure of 360 * this function is an indication that the sockfilt process should terminate. 361 */ 362 363static bool write_stdout(const void *buffer, size_t nbytes) 364{ 365 ssize_t nwrite = fullwrite(fileno(stdout), buffer, nbytes); 366 if(nwrite != (ssize_t)nbytes) { 367 logmsg("exiting..."); 368 return FALSE; 369 } 370 return TRUE; 371} 372 373static void lograw(unsigned char *buffer, ssize_t len) 374{ 375 char data[120]; 376 ssize_t i; 377 unsigned char *ptr = buffer; 378 char *optr = data; 379 ssize_t width=0; 380 381 for(i=0; i<len; i++) { 382 switch(ptr[i]) { 383 case '\n': 384 sprintf(optr, "\\n"); 385 width += 2; 386 optr += 2; 387 break; 388 case '\r': 389 sprintf(optr, "\\r"); 390 width += 2; 391 optr += 2; 392 break; 393 default: 394 sprintf(optr, "%c", (ISGRAPH(ptr[i]) || ptr[i]==0x20) ?ptr[i]:'.'); 395 width++; 396 optr++; 397 break; 398 } 399 400 if(width>60) { 401 logmsg("'%s'", data); 402 width = 0; 403 optr = data; 404 } 405 } 406 if(width) 407 logmsg("'%s'", data); 408} 409 410/* 411 sockfdp is a pointer to an established stream or CURL_SOCKET_BAD 412 413 if sockfd is CURL_SOCKET_BAD, listendfd is a listening socket we must 414 accept() 415*/ 416static bool juggle(curl_socket_t *sockfdp, 417 curl_socket_t listenfd, 418 enum sockmode *mode) 419{ 420 struct timeval timeout; 421 fd_set fds_read; 422 fd_set fds_write; 423 fd_set fds_err; 424 curl_socket_t sockfd = CURL_SOCKET_BAD; 425 curl_socket_t maxfd = CURL_SOCKET_BAD; 426 ssize_t rc; 427 ssize_t nread_socket; 428 ssize_t bytes_written; 429 ssize_t buffer_len; 430 int error = 0; 431 432 /* 'buffer' is this excessively large only to be able to support things like 433 test 1003 which tests exceedingly large server response lines */ 434 unsigned char buffer[17010]; 435 char data[16]; 436 437 if(got_exit_signal) { 438 logmsg("signalled to die, exiting..."); 439 return FALSE; 440 } 441 442#ifdef HAVE_GETPPID 443 /* As a last resort, quit if sockfilt process becomes orphan. Just in case 444 parent ftpserver process has died without killing its sockfilt children */ 445 if(getppid() <= 1) { 446 logmsg("process becomes orphan, exiting"); 447 return FALSE; 448 } 449#endif 450 451 timeout.tv_sec = 120; 452 timeout.tv_usec = 0; 453 454 FD_ZERO(&fds_read); 455 FD_ZERO(&fds_write); 456 FD_ZERO(&fds_err); 457 458#ifdef USE_WINSOCK 459 /* 460 ** WinSock select() does not support standard file descriptors, 461 ** it can only check SOCKETs. Since this program in its current 462 ** state will not work on WinSock based systems, next line is 463 ** commented out to allow warning-free compilation awaiting the 464 ** day it will be fixed to also run on WinSock systems. 465 */ 466#else 467 FD_SET(fileno(stdin), &fds_read); 468#endif 469 470 switch(*mode) { 471 472 case PASSIVE_LISTEN: 473 474 /* server mode */ 475 sockfd = listenfd; 476 /* there's always a socket to wait for */ 477 FD_SET(sockfd, &fds_read); 478 maxfd = sockfd; 479 break; 480 481 case PASSIVE_CONNECT: 482 483 sockfd = *sockfdp; 484 if(CURL_SOCKET_BAD == sockfd) { 485 /* eeek, we are supposedly connected and then this cannot be -1 ! */ 486 logmsg("socket is -1! on %s:%d", __FILE__, __LINE__); 487 maxfd = 0; /* stdin */ 488 } 489 else { 490 /* there's always a socket to wait for */ 491 FD_SET(sockfd, &fds_read); 492 maxfd = sockfd; 493 } 494 break; 495 496 case ACTIVE: 497 498 sockfd = *sockfdp; 499 /* sockfd turns CURL_SOCKET_BAD when our connection has been closed */ 500 if(CURL_SOCKET_BAD != sockfd) { 501 FD_SET(sockfd, &fds_read); 502 maxfd = sockfd; 503 } 504 else { 505 logmsg("No socket to read on"); 506 maxfd = 0; 507 } 508 break; 509 510 case ACTIVE_DISCONNECT: 511 512 logmsg("disconnected, no socket to read on"); 513 maxfd = 0; 514 sockfd = CURL_SOCKET_BAD; 515 break; 516 517 } /* switch(*mode) */ 518 519 520 do { 521 522 rc = select((int)maxfd + 1, &fds_read, &fds_write, &fds_err, &timeout); 523 524 if(got_exit_signal) { 525 logmsg("signalled to die, exiting..."); 526 return FALSE; 527 } 528 529 } while((rc == -1) && ((error = SOCKERRNO) == EINTR)); 530 531 if(rc < 0) { 532 logmsg("select() failed with error: (%d) %s", 533 error, strerror(error)); 534 return FALSE; 535 } 536 537 if(rc == 0) 538 /* timeout */ 539 return TRUE; 540 541 542 if(FD_ISSET(fileno(stdin), &fds_read)) { 543 /* read from stdin, commands/data to be dealt with and possibly passed on 544 to the socket 545 546 protocol: 547 548 4 letter command + LF [mandatory] 549 550 4-digit hexadecimal data length + LF [if the command takes data] 551 data [the data being as long as set above] 552 553 Commands: 554 555 DATA - plain pass-thru data 556 */ 557 558 if(!read_stdin(buffer, 5)) 559 return FALSE; 560 561 logmsg("Received %c%c%c%c (on stdin)", 562 buffer[0], buffer[1], buffer[2], buffer[3] ); 563 564 if(!memcmp("PING", buffer, 4)) { 565 /* send reply on stdout, just proving we are alive */ 566 if(!write_stdout("PONG\n", 5)) 567 return FALSE; 568 } 569 570 else if(!memcmp("PORT", buffer, 4)) { 571 /* Question asking us what PORT number we are listening to. 572 Replies to PORT with "IPv[num]/[port]" */ 573 sprintf((char *)buffer, "%s/%hu\n", ipv_inuse, port); 574 buffer_len = (ssize_t)strlen((char *)buffer); 575 snprintf(data, sizeof(data), "PORT\n%04zx\n", buffer_len); 576 if(!write_stdout(data, 10)) 577 return FALSE; 578 if(!write_stdout(buffer, buffer_len)) 579 return FALSE; 580 } 581 else if(!memcmp("QUIT", buffer, 4)) { 582 /* just die */ 583 logmsg("quits"); 584 return FALSE; 585 } 586 else if(!memcmp("DATA", buffer, 4)) { 587 /* data IN => data OUT */ 588 589 if(!read_stdin(buffer, 5)) 590 return FALSE; 591 592 buffer[5] = '\0'; 593 594 buffer_len = (ssize_t)strtol((char *)buffer, NULL, 16); 595 if (buffer_len > (ssize_t)sizeof(buffer)) { 596 logmsg("ERROR: Buffer size (%zu bytes) too small for data size " 597 "(%zd bytes)", sizeof(buffer), buffer_len); 598 return FALSE; 599 } 600 logmsg("> %zd bytes data, server => client", buffer_len); 601 602 if(!read_stdin(buffer, buffer_len)) 603 return FALSE; 604 605 lograw(buffer, buffer_len); 606 607 if(*mode == PASSIVE_LISTEN) { 608 logmsg("*** We are disconnected!"); 609 if(!write_stdout("DISC\n", 5)) 610 return FALSE; 611 } 612 else { 613 /* send away on the socket */ 614 bytes_written = swrite(sockfd, buffer, buffer_len); 615 if(bytes_written != buffer_len) { 616 logmsg("Not all data was sent. Bytes to send: %zd sent: %zd", 617 buffer_len, bytes_written); 618 } 619 } 620 } 621 else if(!memcmp("DISC", buffer, 4)) { 622 /* disconnect! */ 623 if(!write_stdout("DISC\n", 5)) 624 return FALSE; 625 if(sockfd != CURL_SOCKET_BAD) { 626 logmsg("====> Client forcibly disconnected"); 627 sclose(sockfd); 628 *sockfdp = CURL_SOCKET_BAD; 629 if(*mode == PASSIVE_CONNECT) 630 *mode = PASSIVE_LISTEN; 631 else 632 *mode = ACTIVE_DISCONNECT; 633 } 634 else 635 logmsg("attempt to close already dead connection"); 636 return TRUE; 637 } 638 } 639 640 641 if((sockfd != CURL_SOCKET_BAD) && (FD_ISSET(sockfd, &fds_read)) ) { 642 643 if(*mode == PASSIVE_LISTEN) { 644 /* there's no stream set up yet, this is an indication that there's a 645 client connecting. */ 646 sockfd = accept(sockfd, NULL, NULL); 647 if(CURL_SOCKET_BAD == sockfd) 648 logmsg("accept() failed"); 649 else { 650 logmsg("====> Client connect"); 651 if(!write_stdout("CNCT\n", 5)) 652 return FALSE; 653 *sockfdp = sockfd; /* store the new socket */ 654 *mode = PASSIVE_CONNECT; /* we have connected */ 655 } 656 return TRUE; 657 } 658 659 /* read from socket, pass on data to stdout */ 660 nread_socket = sread(sockfd, buffer, sizeof(buffer)); 661 662 if(nread_socket <= 0) { 663 logmsg("====> Client disconnect"); 664 if(!write_stdout("DISC\n", 5)) 665 return FALSE; 666 sclose(sockfd); 667 *sockfdp = CURL_SOCKET_BAD; 668 if(*mode == PASSIVE_CONNECT) 669 *mode = PASSIVE_LISTEN; 670 else 671 *mode = ACTIVE_DISCONNECT; 672 return TRUE; 673 } 674 675 snprintf(data, sizeof(data), "DATA\n%04zx\n", nread_socket); 676 if(!write_stdout(data, 10)) 677 return FALSE; 678 if(!write_stdout(buffer, nread_socket)) 679 return FALSE; 680 681 logmsg("< %zd bytes data, client => server", nread_socket); 682 lograw(buffer, nread_socket); 683 } 684 685 return TRUE; 686} 687 688static curl_socket_t sockdaemon(curl_socket_t sock, 689 unsigned short *listenport) 690{ 691 /* passive daemon style */ 692 srvr_sockaddr_union_t listener; 693 int flag; 694 int rc; 695 int totdelay = 0; 696 int maxretr = 10; 697 int delay= 20; 698 int attempt = 0; 699 int error = 0; 700 701 do { 702 attempt++; 703 flag = 1; 704 rc = setsockopt(sock, SOL_SOCKET, SO_REUSEADDR, 705 (void *)&flag, sizeof(flag)); 706 if(rc) { 707 error = SOCKERRNO; 708 logmsg("setsockopt(SO_REUSEADDR) failed with error: (%d) %s", 709 error, strerror(error)); 710 if(maxretr) { 711 rc = wait_ms(delay); 712 if(rc) { 713 /* should not happen */ 714 error = SOCKERRNO; 715 logmsg("wait_ms() failed with error: (%d) %s", 716 error, strerror(error)); 717 sclose(sock); 718 return CURL_SOCKET_BAD; 719 } 720 if(got_exit_signal) { 721 logmsg("signalled to die, exiting..."); 722 sclose(sock); 723 return CURL_SOCKET_BAD; 724 } 725 totdelay += delay; 726 delay *= 2; /* double the sleep for next attempt */ 727 } 728 } 729 } while(rc && maxretr--); 730 731 if(rc) { 732 logmsg("setsockopt(SO_REUSEADDR) failed %d times in %d ms. Error: (%d) %s", 733 attempt, totdelay, error, strerror(error)); 734 logmsg("Continuing anyway..."); 735 } 736 737 /* When the specified listener port is zero, it is actually a 738 request to let the system choose a non-zero available port. */ 739 740#ifdef ENABLE_IPV6 741 if(!use_ipv6) { 742#endif 743 memset(&listener.sa4, 0, sizeof(listener.sa4)); 744 listener.sa4.sin_family = AF_INET; 745 listener.sa4.sin_addr.s_addr = INADDR_ANY; 746 listener.sa4.sin_port = htons(*listenport); 747 rc = bind(sock, &listener.sa, sizeof(listener.sa4)); 748#ifdef ENABLE_IPV6 749 } 750 else { 751 memset(&listener.sa6, 0, sizeof(listener.sa6)); 752 listener.sa6.sin6_family = AF_INET6; 753 listener.sa6.sin6_addr = in6addr_any; 754 listener.sa6.sin6_port = htons(*listenport); 755 rc = bind(sock, &listener.sa, sizeof(listener.sa6)); 756 } 757#endif /* ENABLE_IPV6 */ 758 if(rc) { 759 error = SOCKERRNO; 760 logmsg("Error binding socket on port %hu: (%d) %s", 761 *listenport, error, strerror(error)); 762 sclose(sock); 763 return CURL_SOCKET_BAD; 764 } 765 766 if(!*listenport) { 767 /* The system was supposed to choose a port number, figure out which 768 port we actually got and update the listener port value with it. */ 769 curl_socklen_t la_size; 770 srvr_sockaddr_union_t localaddr; 771#ifdef ENABLE_IPV6 772 if(!use_ipv6) 773#endif 774 la_size = sizeof(localaddr.sa4); 775#ifdef ENABLE_IPV6 776 else 777 la_size = sizeof(localaddr.sa6); 778#endif 779 memset(&localaddr.sa, 0, (size_t)la_size); 780 if(getsockname(sock, &localaddr.sa, &la_size) < 0) { 781 error = SOCKERRNO; 782 logmsg("getsockname() failed with error: (%d) %s", 783 error, strerror(error)); 784 sclose(sock); 785 return CURL_SOCKET_BAD; 786 } 787 switch (localaddr.sa.sa_family) { 788 case AF_INET: 789 *listenport = ntohs(localaddr.sa4.sin_port); 790 break; 791#ifdef ENABLE_IPV6 792 case AF_INET6: 793 *listenport = ntohs(localaddr.sa6.sin6_port); 794 break; 795#endif 796 default: 797 break; 798 } 799 if(!*listenport) { 800 /* Real failure, listener port shall not be zero beyond this point. */ 801 logmsg("Apparently getsockname() succeeded, with listener port zero."); 802 logmsg("A valid reason for this failure is a binary built without"); 803 logmsg("proper network library linkage. This might not be the only"); 804 logmsg("reason, but double check it before anything else."); 805 sclose(sock); 806 return CURL_SOCKET_BAD; 807 } 808 } 809 810 /* start accepting connections */ 811 rc = listen(sock, 5); 812 if(0 != rc) { 813 error = SOCKERRNO; 814 logmsg("listen() failed with error: (%d) %s", 815 error, strerror(error)); 816 sclose(sock); 817 return CURL_SOCKET_BAD; 818 } 819 820 return sock; 821} 822 823 824int main(int argc, char *argv[]) 825{ 826 srvr_sockaddr_union_t me; 827 curl_socket_t sock = CURL_SOCKET_BAD; 828 curl_socket_t msgsock = CURL_SOCKET_BAD; 829 int wrotepidfile = 0; 830 char *pidname= (char *)".sockfilt.pid"; 831 bool juggle_again; 832 int rc; 833 int error; 834 int arg=1; 835 enum sockmode mode = PASSIVE_LISTEN; /* default */ 836 const char *addr = NULL; 837 838 while(argc>arg) { 839 if(!strcmp("--version", argv[arg])) { 840 printf("sockfilt IPv4%s\n", 841#ifdef ENABLE_IPV6 842 "/IPv6" 843#else 844 "" 845#endif 846 ); 847 return 0; 848 } 849 else if(!strcmp("--verbose", argv[arg])) { 850 verbose = TRUE; 851 arg++; 852 } 853 else if(!strcmp("--pidfile", argv[arg])) { 854 arg++; 855 if(argc>arg) 856 pidname = argv[arg++]; 857 } 858 else if(!strcmp("--logfile", argv[arg])) { 859 arg++; 860 if(argc>arg) 861 serverlogfile = argv[arg++]; 862 } 863 else if(!strcmp("--ipv6", argv[arg])) { 864#ifdef ENABLE_IPV6 865 ipv_inuse = "IPv6"; 866 use_ipv6 = TRUE; 867#endif 868 arg++; 869 } 870 else if(!strcmp("--ipv4", argv[arg])) { 871 /* for completeness, we support this option as well */ 872#ifdef ENABLE_IPV6 873 ipv_inuse = "IPv4"; 874 use_ipv6 = FALSE; 875#endif 876 arg++; 877 } 878 else if(!strcmp("--port", argv[arg])) { 879 arg++; 880 if(argc>arg) { 881 char *endptr; 882 unsigned long ulnum = strtoul(argv[arg], &endptr, 10); 883 if((endptr != argv[arg] + strlen(argv[arg])) || 884 ((ulnum != 0UL) && ((ulnum < 1025UL) || (ulnum > 65535UL)))) { 885 fprintf(stderr, "sockfilt: invalid --port argument (%s)\n", 886 argv[arg]); 887 return 0; 888 } 889 port = curlx_ultous(ulnum); 890 arg++; 891 } 892 } 893 else if(!strcmp("--connect", argv[arg])) { 894 /* Asked to actively connect to the specified local port instead of 895 doing a passive server-style listening. */ 896 arg++; 897 if(argc>arg) { 898 char *endptr; 899 unsigned long ulnum = strtoul(argv[arg], &endptr, 10); 900 if((endptr != argv[arg] + strlen(argv[arg])) || 901 (ulnum < 1025UL) || (ulnum > 65535UL)) { 902 fprintf(stderr, "sockfilt: invalid --connect argument (%s)\n", 903 argv[arg]); 904 return 0; 905 } 906 connectport = curlx_ultous(ulnum); 907 arg++; 908 } 909 } 910 else if(!strcmp("--addr", argv[arg])) { 911 /* Set an IP address to use with --connect; otherwise use localhost */ 912 arg++; 913 if(argc>arg) { 914 addr = argv[arg]; 915 arg++; 916 } 917 } 918 else { 919 puts("Usage: sockfilt [option]\n" 920 " --version\n" 921 " --verbose\n" 922 " --logfile [file]\n" 923 " --pidfile [file]\n" 924 " --ipv4\n" 925 " --ipv6\n" 926 " --port [port]\n" 927 " --connect [port]\n" 928 " --addr [address]"); 929 return 0; 930 } 931 } 932 933#ifdef WIN32 934 win32_init(); 935 atexit(win32_cleanup); 936#endif 937 938 install_signal_handlers(); 939 940#ifdef ENABLE_IPV6 941 if(!use_ipv6) 942#endif 943 sock = socket(AF_INET, SOCK_STREAM, 0); 944#ifdef ENABLE_IPV6 945 else 946 sock = socket(AF_INET6, SOCK_STREAM, 0); 947#endif 948 949 if(CURL_SOCKET_BAD == sock) { 950 error = SOCKERRNO; 951 logmsg("Error creating socket: (%d) %s", 952 error, strerror(error)); 953 goto sockfilt_cleanup; 954 } 955 956 if(connectport) { 957 /* Active mode, we should connect to the given port number */ 958 mode = ACTIVE; 959#ifdef ENABLE_IPV6 960 if(!use_ipv6) { 961#endif 962 memset(&me.sa4, 0, sizeof(me.sa4)); 963 me.sa4.sin_family = AF_INET; 964 me.sa4.sin_port = htons(connectport); 965 me.sa4.sin_addr.s_addr = INADDR_ANY; 966 if (!addr) 967 addr = "127.0.0.1"; 968 Curl_inet_pton(AF_INET, addr, &me.sa4.sin_addr); 969 970 rc = connect(sock, &me.sa, sizeof(me.sa4)); 971#ifdef ENABLE_IPV6 972 } 973 else { 974 memset(&me.sa6, 0, sizeof(me.sa6)); 975 me.sa6.sin6_family = AF_INET6; 976 me.sa6.sin6_port = htons(connectport); 977 if (!addr) 978 addr = "::1"; 979 Curl_inet_pton(AF_INET6, addr, &me.sa6.sin6_addr); 980 981 rc = connect(sock, &me.sa, sizeof(me.sa6)); 982 } 983#endif /* ENABLE_IPV6 */ 984 if(rc) { 985 error = SOCKERRNO; 986 logmsg("Error connecting to port %hu: (%d) %s", 987 connectport, error, strerror(error)); 988 goto sockfilt_cleanup; 989 } 990 logmsg("====> Client connect"); 991 msgsock = sock; /* use this as stream */ 992 } 993 else { 994 /* passive daemon style */ 995 sock = sockdaemon(sock, &port); 996 if(CURL_SOCKET_BAD == sock) 997 goto sockfilt_cleanup; 998 msgsock = CURL_SOCKET_BAD; /* no stream socket yet */ 999 } 1000 1001 logmsg("Running %s version", ipv_inuse); 1002 1003 if(connectport) 1004 logmsg("Connected to port %hu", connectport); 1005 else 1006 logmsg("Listening on port %hu", port); 1007 1008 wrotepidfile = write_pidfile(pidname); 1009 if(!wrotepidfile) 1010 goto sockfilt_cleanup; 1011 1012 do { 1013 juggle_again = juggle(&msgsock, sock, &mode); 1014 } while(juggle_again); 1015 1016sockfilt_cleanup: 1017 1018 if((msgsock != sock) && (msgsock != CURL_SOCKET_BAD)) 1019 sclose(msgsock); 1020 1021 if(sock != CURL_SOCKET_BAD) 1022 sclose(sock); 1023 1024 if(wrotepidfile) 1025 unlink(pidname); 1026 1027 restore_signal_handlers(); 1028 1029 if(got_exit_signal) { 1030 logmsg("============> sockfilt exits with signal (%d)", exit_signal); 1031 /* 1032 * To properly set the return status of the process we 1033 * must raise the same signal SIGINT or SIGTERM that we 1034 * caught and let the old handler take care of it. 1035 */ 1036 raise(exit_signal); 1037 } 1038 1039 logmsg("============> sockfilt quits"); 1040 return 0; 1041} 1042 1043