1/*************************************************************************** 2 * _ _ ____ _ 3 * Project ___| | | | _ \| | 4 * / __| | | | |_) | | 5 * | (__| |_| | _ <| |___ 6 * \___|\___/|_| \_\_____| 7 * 8 * Copyright (C) 1998 - 2011, 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; 126static bool bind_only = FALSE; 127#ifdef ENABLE_IPV6 128static bool use_ipv6 = FALSE; 129#endif 130static const char *ipv_inuse = "IPv4"; 131static unsigned short port = DEFAULT_PORT; 132static unsigned short connectport = 0; /* if non-zero, we activate this mode */ 133 134enum sockmode { 135 PASSIVE_LISTEN, /* as a server waiting for connections */ 136 PASSIVE_CONNECT, /* as a server, connected to a client */ 137 ACTIVE, /* as a client, connected to a server */ 138 ACTIVE_DISCONNECT /* as a client, disconnected from server */ 139}; 140 141/* do-nothing macro replacement for systems which lack siginterrupt() */ 142 143#ifndef HAVE_SIGINTERRUPT 144#define siginterrupt(x,y) do {} while(0) 145#endif 146 147/* vars used to keep around previous signal handlers */ 148 149typedef RETSIGTYPE (*SIGHANDLER_T)(int); 150 151#ifdef SIGHUP 152static SIGHANDLER_T old_sighup_handler = SIG_ERR; 153#endif 154 155#ifdef SIGPIPE 156static SIGHANDLER_T old_sigpipe_handler = SIG_ERR; 157#endif 158 159#ifdef SIGALRM 160static SIGHANDLER_T old_sigalrm_handler = SIG_ERR; 161#endif 162 163#ifdef SIGINT 164static SIGHANDLER_T old_sigint_handler = SIG_ERR; 165#endif 166 167#ifdef SIGTERM 168static SIGHANDLER_T old_sigterm_handler = SIG_ERR; 169#endif 170 171/* var which if set indicates that the program should finish execution */ 172 173SIG_ATOMIC_T got_exit_signal = 0; 174 175/* if next is set indicates the first signal handled in exit_signal_handler */ 176 177static volatile int exit_signal = 0; 178 179/* signal handler that will be triggered to indicate that the program 180 should finish its execution in a controlled manner as soon as possible. 181 The first time this is called it will set got_exit_signal to one and 182 store in exit_signal the signal that triggered its execution. */ 183 184static RETSIGTYPE exit_signal_handler(int signum) 185{ 186 int old_errno = ERRNO; 187 if(got_exit_signal == 0) { 188 got_exit_signal = 1; 189 exit_signal = signum; 190 } 191 (void)signal(signum, exit_signal_handler); 192 SET_ERRNO(old_errno); 193} 194 195static void install_signal_handlers(void) 196{ 197#ifdef SIGHUP 198 /* ignore SIGHUP signal */ 199 if((old_sighup_handler = signal(SIGHUP, SIG_IGN)) == SIG_ERR) 200 logmsg("cannot install SIGHUP handler: %s", strerror(ERRNO)); 201#endif 202#ifdef SIGPIPE 203 /* ignore SIGPIPE signal */ 204 if((old_sigpipe_handler = signal(SIGPIPE, SIG_IGN)) == SIG_ERR) 205 logmsg("cannot install SIGPIPE handler: %s", strerror(ERRNO)); 206#endif 207#ifdef SIGALRM 208 /* ignore SIGALRM signal */ 209 if((old_sigalrm_handler = signal(SIGALRM, SIG_IGN)) == SIG_ERR) 210 logmsg("cannot install SIGALRM handler: %s", strerror(ERRNO)); 211#endif 212#ifdef SIGINT 213 /* handle SIGINT signal with our exit_signal_handler */ 214 if((old_sigint_handler = signal(SIGINT, exit_signal_handler)) == SIG_ERR) 215 logmsg("cannot install SIGINT handler: %s", strerror(ERRNO)); 216 else 217 siginterrupt(SIGINT, 1); 218#endif 219#ifdef SIGTERM 220 /* handle SIGTERM signal with our exit_signal_handler */ 221 if((old_sigterm_handler = signal(SIGTERM, exit_signal_handler)) == SIG_ERR) 222 logmsg("cannot install SIGTERM handler: %s", strerror(ERRNO)); 223 else 224 siginterrupt(SIGTERM, 1); 225#endif 226} 227 228static void restore_signal_handlers(void) 229{ 230#ifdef SIGHUP 231 if(SIG_ERR != old_sighup_handler) 232 (void)signal(SIGHUP, old_sighup_handler); 233#endif 234#ifdef SIGPIPE 235 if(SIG_ERR != old_sigpipe_handler) 236 (void)signal(SIGPIPE, old_sigpipe_handler); 237#endif 238#ifdef SIGALRM 239 if(SIG_ERR != old_sigalrm_handler) 240 (void)signal(SIGALRM, old_sigalrm_handler); 241#endif 242#ifdef SIGINT 243 if(SIG_ERR != old_sigint_handler) 244 (void)signal(SIGINT, old_sigint_handler); 245#endif 246#ifdef SIGTERM 247 if(SIG_ERR != old_sigterm_handler) 248 (void)signal(SIGTERM, old_sigterm_handler); 249#endif 250} 251 252/* 253 * fullread is a wrapper around the read() function. This will repeat the call 254 * to read() until it actually has read the complete number of bytes indicated 255 * in nbytes or it fails with a condition that cannot be handled with a simple 256 * retry of the read call. 257 */ 258 259static ssize_t fullread(int filedes, void *buffer, size_t nbytes) 260{ 261 int error; 262 ssize_t rc; 263 ssize_t nread = 0; 264 265 do { 266 rc = read(filedes, (unsigned char *)buffer + nread, nbytes - nread); 267 268 if(got_exit_signal) { 269 logmsg("signalled to die"); 270 return -1; 271 } 272 273 if(rc < 0) { 274 error = ERRNO; 275 if((error == EINTR) || (error == EAGAIN)) 276 continue; 277 logmsg("unrecoverable read() failure: %s", strerror(error)); 278 return -1; 279 } 280 281 if(rc == 0) { 282 logmsg("got 0 reading from stdin"); 283 return 0; 284 } 285 286 nread += rc; 287 288 } while((size_t)nread < nbytes); 289 290 if(verbose) 291 logmsg("read %zd bytes", nread); 292 293 return nread; 294} 295 296/* 297 * fullwrite is a wrapper around the write() function. This will repeat the 298 * call to write() until it actually has written the complete number of bytes 299 * indicated in nbytes or it fails with a condition that cannot be handled 300 * with a simple retry of the write call. 301 */ 302 303static ssize_t fullwrite(int filedes, const void *buffer, size_t nbytes) 304{ 305 int error; 306 ssize_t wc; 307 ssize_t nwrite = 0; 308 309 do { 310 wc = write(filedes, (unsigned char *)buffer + nwrite, nbytes - nwrite); 311 312 if(got_exit_signal) { 313 logmsg("signalled to die"); 314 return -1; 315 } 316 317 if(wc < 0) { 318 error = ERRNO; 319 if((error == EINTR) || (error == EAGAIN)) 320 continue; 321 logmsg("unrecoverable write() failure: %s", strerror(error)); 322 return -1; 323 } 324 325 if(wc == 0) { 326 logmsg("put 0 writing to stdout"); 327 return 0; 328 } 329 330 nwrite += wc; 331 332 } while((size_t)nwrite < nbytes); 333 334 if(verbose) 335 logmsg("wrote %zd bytes", nwrite); 336 337 return nwrite; 338} 339 340/* 341 * read_stdin tries to read from stdin nbytes into the given buffer. This is a 342 * blocking function that will only return TRUE when nbytes have actually been 343 * read or FALSE when an unrecoverable error has been detected. Failure of this 344 * function is an indication that the sockfilt process should terminate. 345 */ 346 347static bool read_stdin(void *buffer, size_t nbytes) 348{ 349 ssize_t nread = fullread(fileno(stdin), buffer, nbytes); 350 if(nread != (ssize_t)nbytes) { 351 logmsg("exiting..."); 352 return FALSE; 353 } 354 return TRUE; 355} 356 357/* 358 * write_stdout tries to write to stdio nbytes from the given buffer. This is a 359 * blocking function that will only return TRUE when nbytes have actually been 360 * written or FALSE when an unrecoverable error has been detected. Failure of 361 * this function is an indication that the sockfilt process should terminate. 362 */ 363 364static bool write_stdout(const void *buffer, size_t nbytes) 365{ 366 ssize_t nwrite = fullwrite(fileno(stdout), buffer, nbytes); 367 if(nwrite != (ssize_t)nbytes) { 368 logmsg("exiting..."); 369 return FALSE; 370 } 371 return TRUE; 372} 373 374static void lograw(unsigned char *buffer, ssize_t len) 375{ 376 char data[120]; 377 ssize_t i; 378 unsigned char *ptr = buffer; 379 char *optr = data; 380 ssize_t width=0; 381 382 for(i=0; i<len; i++) { 383 switch(ptr[i]) { 384 case '\n': 385 sprintf(optr, "\\n"); 386 width += 2; 387 optr += 2; 388 break; 389 case '\r': 390 sprintf(optr, "\\r"); 391 width += 2; 392 optr += 2; 393 break; 394 default: 395 sprintf(optr, "%c", (ISGRAPH(ptr[i]) || ptr[i]==0x20) ?ptr[i]:'.'); 396 width++; 397 optr++; 398 break; 399 } 400 401 if(width>60) { 402 logmsg("'%s'", data); 403 width = 0; 404 optr = data; 405 } 406 } 407 if(width) 408 logmsg("'%s'", data); 409} 410 411/* 412 sockfdp is a pointer to an established stream or CURL_SOCKET_BAD 413 414 if sockfd is CURL_SOCKET_BAD, listendfd is a listening socket we must 415 accept() 416*/ 417static bool juggle(curl_socket_t *sockfdp, 418 curl_socket_t listenfd, 419 enum sockmode *mode) 420{ 421 struct timeval timeout; 422 fd_set fds_read; 423 fd_set fds_write; 424 fd_set fds_err; 425 curl_socket_t sockfd = CURL_SOCKET_BAD; 426 curl_socket_t maxfd = CURL_SOCKET_BAD; 427 ssize_t rc; 428 ssize_t nread_socket; 429 ssize_t bytes_written; 430 ssize_t buffer_len; 431 int error = 0; 432 433 /* 'buffer' is this excessively large only to be able to support things like 434 test 1003 which tests exceedingly large server response lines */ 435 unsigned char buffer[17010]; 436 char data[16]; 437 438 if(got_exit_signal) { 439 logmsg("signalled to die, exiting..."); 440 return FALSE; 441 } 442 443#ifdef HAVE_GETPPID 444 /* As a last resort, quit if sockfilt process becomes orphan. Just in case 445 parent ftpserver process has died without killing its sockfilt children */ 446 if(getppid() <= 1) { 447 logmsg("process becomes orphan, exiting"); 448 return FALSE; 449 } 450#endif 451 452 timeout.tv_sec = 120; 453 timeout.tv_usec = 0; 454 455 FD_ZERO(&fds_read); 456 FD_ZERO(&fds_write); 457 FD_ZERO(&fds_err); 458 459#ifdef USE_WINSOCK 460 /* 461 ** WinSock select() does not support standard file descriptors, 462 ** it can only check SOCKETs. Since this program in its current 463 ** state will not work on WinSock based systems, next line is 464 ** commented out to allow warning-free compilation awaiting the 465 ** day it will be fixed to also run on WinSock systems. 466 */ 467#else 468 FD_SET(fileno(stdin), &fds_read); 469#endif 470 471 switch(*mode) { 472 473 case PASSIVE_LISTEN: 474 475 /* server mode */ 476 sockfd = listenfd; 477 /* there's always a socket to wait for */ 478 FD_SET(sockfd, &fds_read); 479 maxfd = sockfd; 480 break; 481 482 case PASSIVE_CONNECT: 483 484 sockfd = *sockfdp; 485 if(CURL_SOCKET_BAD == sockfd) { 486 /* eeek, we are supposedly connected and then this cannot be -1 ! */ 487 logmsg("socket is -1! on %s:%d", __FILE__, __LINE__); 488 maxfd = 0; /* stdin */ 489 } 490 else { 491 /* there's always a socket to wait for */ 492 FD_SET(sockfd, &fds_read); 493 maxfd = sockfd; 494 } 495 break; 496 497 case ACTIVE: 498 499 sockfd = *sockfdp; 500 /* sockfd turns CURL_SOCKET_BAD when our connection has been closed */ 501 if(CURL_SOCKET_BAD != sockfd) { 502 FD_SET(sockfd, &fds_read); 503 maxfd = sockfd; 504 } 505 else { 506 logmsg("No socket to read on"); 507 maxfd = 0; 508 } 509 break; 510 511 case ACTIVE_DISCONNECT: 512 513 logmsg("disconnected, no socket to read on"); 514 maxfd = 0; 515 sockfd = CURL_SOCKET_BAD; 516 break; 517 518 } /* switch(*mode) */ 519 520 521 do { 522 523 rc = select((int)maxfd + 1, &fds_read, &fds_write, &fds_err, &timeout); 524 525 if(got_exit_signal) { 526 logmsg("signalled to die, exiting..."); 527 return FALSE; 528 } 529 530 } while((rc == -1) && ((error = SOCKERRNO) == EINTR)); 531 532 if(rc < 0) { 533 logmsg("select() failed with error: (%d) %s", 534 error, strerror(error)); 535 return FALSE; 536 } 537 538 if(rc == 0) 539 /* timeout */ 540 return TRUE; 541 542 543 if(FD_ISSET(fileno(stdin), &fds_read)) { 544 /* read from stdin, commands/data to be dealt with and possibly passed on 545 to the socket 546 547 protocol: 548 549 4 letter command + LF [mandatory] 550 551 4-digit hexadecimal data length + LF [if the command takes data] 552 data [the data being as long as set above] 553 554 Commands: 555 556 DATA - plain pass-thru data 557 */ 558 559 if(!read_stdin(buffer, 5)) 560 return FALSE; 561 562 logmsg("Received %c%c%c%c (on stdin)", 563 buffer[0], buffer[1], buffer[2], buffer[3] ); 564 565 if(!memcmp("PING", buffer, 4)) { 566 /* send reply on stdout, just proving we are alive */ 567 if(!write_stdout("PONG\n", 5)) 568 return FALSE; 569 } 570 571 else if(!memcmp("PORT", buffer, 4)) { 572 /* Question asking us what PORT number we are listening to. 573 Replies to PORT with "IPv[num]/[port]" */ 574 sprintf((char *)buffer, "%s/%hu\n", ipv_inuse, port); 575 buffer_len = (ssize_t)strlen((char *)buffer); 576 snprintf(data, sizeof(data), "PORT\n%04zx\n", buffer_len); 577 if(!write_stdout(data, 10)) 578 return FALSE; 579 if(!write_stdout(buffer, buffer_len)) 580 return FALSE; 581 } 582 else if(!memcmp("QUIT", buffer, 4)) { 583 /* just die */ 584 logmsg("quits"); 585 return FALSE; 586 } 587 else if(!memcmp("DATA", buffer, 4)) { 588 /* data IN => data OUT */ 589 590 if(!read_stdin(buffer, 5)) 591 return FALSE; 592 593 buffer[5] = '\0'; 594 595 buffer_len = (ssize_t)strtol((char *)buffer, NULL, 16); 596 if (buffer_len > (ssize_t)sizeof(buffer)) { 597 logmsg("ERROR: Buffer size (%zu bytes) too small for data size " 598 "(%zd bytes)", sizeof(buffer), buffer_len); 599 return FALSE; 600 } 601 logmsg("> %zd bytes data, server => client", buffer_len); 602 603 if(!read_stdin(buffer, buffer_len)) 604 return FALSE; 605 606 lograw(buffer, buffer_len); 607 608 if(*mode == PASSIVE_LISTEN) { 609 logmsg("*** We are disconnected!"); 610 if(!write_stdout("DISC\n", 5)) 611 return FALSE; 612 } 613 else { 614 /* send away on the socket */ 615 bytes_written = swrite(sockfd, buffer, buffer_len); 616 if(bytes_written != buffer_len) { 617 logmsg("Not all data was sent. Bytes to send: %zd sent: %zd", 618 buffer_len, bytes_written); 619 } 620 } 621 } 622 else if(!memcmp("DISC", buffer, 4)) { 623 /* disconnect! */ 624 if(!write_stdout("DISC\n", 5)) 625 return FALSE; 626 if(sockfd != CURL_SOCKET_BAD) { 627 logmsg("====> Client forcibly disconnected"); 628 sclose(sockfd); 629 *sockfdp = CURL_SOCKET_BAD; 630 if(*mode == PASSIVE_CONNECT) 631 *mode = PASSIVE_LISTEN; 632 else 633 *mode = ACTIVE_DISCONNECT; 634 } 635 else 636 logmsg("attempt to close already dead connection"); 637 return TRUE; 638 } 639 } 640 641 642 if((sockfd != CURL_SOCKET_BAD) && (FD_ISSET(sockfd, &fds_read)) ) { 643 644 if(*mode == PASSIVE_LISTEN) { 645 /* there's no stream set up yet, this is an indication that there's a 646 client connecting. */ 647 sockfd = accept(sockfd, NULL, NULL); 648 if(CURL_SOCKET_BAD == sockfd) 649 logmsg("accept() failed"); 650 else { 651 logmsg("====> Client connect"); 652 if(!write_stdout("CNCT\n", 5)) 653 return FALSE; 654 *sockfdp = sockfd; /* store the new socket */ 655 *mode = PASSIVE_CONNECT; /* we have connected */ 656 } 657 return TRUE; 658 } 659 660 /* read from socket, pass on data to stdout */ 661 nread_socket = sread(sockfd, buffer, sizeof(buffer)); 662 663 if(nread_socket <= 0) { 664 logmsg("====> Client disconnect"); 665 if(!write_stdout("DISC\n", 5)) 666 return FALSE; 667 sclose(sockfd); 668 *sockfdp = CURL_SOCKET_BAD; 669 if(*mode == PASSIVE_CONNECT) 670 *mode = PASSIVE_LISTEN; 671 else 672 *mode = ACTIVE_DISCONNECT; 673 return TRUE; 674 } 675 676 snprintf(data, sizeof(data), "DATA\n%04zx\n", nread_socket); 677 if(!write_stdout(data, 10)) 678 return FALSE; 679 if(!write_stdout(buffer, nread_socket)) 680 return FALSE; 681 682 logmsg("< %zd bytes data, client => server", nread_socket); 683 lograw(buffer, nread_socket); 684 } 685 686 return TRUE; 687} 688 689static curl_socket_t sockdaemon(curl_socket_t sock, 690 unsigned short *listenport) 691{ 692 /* passive daemon style */ 693 srvr_sockaddr_union_t listener; 694 int flag; 695 int rc; 696 int totdelay = 0; 697 int maxretr = 10; 698 int delay= 20; 699 int attempt = 0; 700 int error = 0; 701 702 do { 703 attempt++; 704 flag = 1; 705 rc = setsockopt(sock, SOL_SOCKET, SO_REUSEADDR, 706 (void *)&flag, sizeof(flag)); 707 if(rc) { 708 error = SOCKERRNO; 709 logmsg("setsockopt(SO_REUSEADDR) failed with error: (%d) %s", 710 error, strerror(error)); 711 if(maxretr) { 712 rc = wait_ms(delay); 713 if(rc) { 714 /* should not happen */ 715 error = SOCKERRNO; 716 logmsg("wait_ms() failed with error: (%d) %s", 717 error, strerror(error)); 718 sclose(sock); 719 return CURL_SOCKET_BAD; 720 } 721 if(got_exit_signal) { 722 logmsg("signalled to die, exiting..."); 723 sclose(sock); 724 return CURL_SOCKET_BAD; 725 } 726 totdelay += delay; 727 delay *= 2; /* double the sleep for next attempt */ 728 } 729 } 730 } while(rc && maxretr--); 731 732 if(rc) { 733 logmsg("setsockopt(SO_REUSEADDR) failed %d times in %d ms. Error: (%d) %s", 734 attempt, totdelay, error, strerror(error)); 735 logmsg("Continuing anyway..."); 736 } 737 738 /* When the specified listener port is zero, it is actually a 739 request to let the system choose a non-zero available port. */ 740 741#ifdef ENABLE_IPV6 742 if(!use_ipv6) { 743#endif 744 memset(&listener.sa4, 0, sizeof(listener.sa4)); 745 listener.sa4.sin_family = AF_INET; 746 listener.sa4.sin_addr.s_addr = INADDR_ANY; 747 listener.sa4.sin_port = htons(*listenport); 748 rc = bind(sock, &listener.sa, sizeof(listener.sa4)); 749#ifdef ENABLE_IPV6 750 } 751 else { 752 memset(&listener.sa6, 0, sizeof(listener.sa6)); 753 listener.sa6.sin6_family = AF_INET6; 754 listener.sa6.sin6_addr = in6addr_any; 755 listener.sa6.sin6_port = htons(*listenport); 756 rc = bind(sock, &listener.sa, sizeof(listener.sa6)); 757 } 758#endif /* ENABLE_IPV6 */ 759 if(rc) { 760 error = SOCKERRNO; 761 logmsg("Error binding socket on port %hu: (%d) %s", 762 *listenport, error, strerror(error)); 763 sclose(sock); 764 return CURL_SOCKET_BAD; 765 } 766 767 if(!*listenport) { 768 /* The system was supposed to choose a port number, figure out which 769 port we actually got and update the listener port value with it. */ 770 curl_socklen_t la_size; 771 srvr_sockaddr_union_t localaddr; 772#ifdef ENABLE_IPV6 773 if(!use_ipv6) 774#endif 775 la_size = sizeof(localaddr.sa4); 776#ifdef ENABLE_IPV6 777 else 778 la_size = sizeof(localaddr.sa6); 779#endif 780 memset(&localaddr.sa, 0, (size_t)la_size); 781 if(getsockname(sock, &localaddr.sa, &la_size) < 0) { 782 error = SOCKERRNO; 783 logmsg("getsockname() failed with error: (%d) %s", 784 error, strerror(error)); 785 sclose(sock); 786 return CURL_SOCKET_BAD; 787 } 788 switch (localaddr.sa.sa_family) { 789 case AF_INET: 790 *listenport = ntohs(localaddr.sa4.sin_port); 791 break; 792#ifdef ENABLE_IPV6 793 case AF_INET6: 794 *listenport = ntohs(localaddr.sa6.sin6_port); 795 break; 796#endif 797 default: 798 break; 799 } 800 if(!*listenport) { 801 /* Real failure, listener port shall not be zero beyond this point. */ 802 logmsg("Apparently getsockname() succeeded, with listener port zero."); 803 logmsg("A valid reason for this failure is a binary built without"); 804 logmsg("proper network library linkage. This might not be the only"); 805 logmsg("reason, but double check it before anything else."); 806 sclose(sock); 807 return CURL_SOCKET_BAD; 808 } 809 } 810 811 /* bindonly option forces no listening */ 812 if(bind_only) { 813 logmsg("instructed to bind port without listening"); 814 return sock; 815 } 816 817 /* start accepting connections */ 818 rc = listen(sock, 5); 819 if(0 != rc) { 820 error = SOCKERRNO; 821 logmsg("listen() failed with error: (%d) %s", 822 error, strerror(error)); 823 sclose(sock); 824 return CURL_SOCKET_BAD; 825 } 826 827 return sock; 828} 829 830 831int main(int argc, char *argv[]) 832{ 833 srvr_sockaddr_union_t me; 834 curl_socket_t sock = CURL_SOCKET_BAD; 835 curl_socket_t msgsock = CURL_SOCKET_BAD; 836 int wrotepidfile = 0; 837 char *pidname= (char *)".sockfilt.pid"; 838 bool juggle_again; 839 int rc; 840 int error; 841 int arg=1; 842 enum sockmode mode = PASSIVE_LISTEN; /* default */ 843 const char *addr = NULL; 844 845 while(argc>arg) { 846 if(!strcmp("--version", argv[arg])) { 847 printf("sockfilt IPv4%s\n", 848#ifdef ENABLE_IPV6 849 "/IPv6" 850#else 851 "" 852#endif 853 ); 854 return 0; 855 } 856 else if(!strcmp("--verbose", argv[arg])) { 857 verbose = TRUE; 858 arg++; 859 } 860 else if(!strcmp("--pidfile", argv[arg])) { 861 arg++; 862 if(argc>arg) 863 pidname = argv[arg++]; 864 } 865 else if(!strcmp("--logfile", argv[arg])) { 866 arg++; 867 if(argc>arg) 868 serverlogfile = argv[arg++]; 869 } 870 else if(!strcmp("--ipv6", argv[arg])) { 871#ifdef ENABLE_IPV6 872 ipv_inuse = "IPv6"; 873 use_ipv6 = TRUE; 874#endif 875 arg++; 876 } 877 else if(!strcmp("--ipv4", argv[arg])) { 878 /* for completeness, we support this option as well */ 879#ifdef ENABLE_IPV6 880 ipv_inuse = "IPv4"; 881 use_ipv6 = FALSE; 882#endif 883 arg++; 884 } 885 else if(!strcmp("--bindonly", argv[arg])) { 886 bind_only = TRUE; 887 arg++; 888 } 889 else if(!strcmp("--port", argv[arg])) { 890 arg++; 891 if(argc>arg) { 892 char *endptr; 893 unsigned long ulnum = strtoul(argv[arg], &endptr, 10); 894 if((endptr != argv[arg] + strlen(argv[arg])) || 895 ((ulnum != 0UL) && ((ulnum < 1025UL) || (ulnum > 65535UL)))) { 896 fprintf(stderr, "sockfilt: invalid --port argument (%s)\n", 897 argv[arg]); 898 return 0; 899 } 900 port = curlx_ultous(ulnum); 901 arg++; 902 } 903 } 904 else if(!strcmp("--connect", argv[arg])) { 905 /* Asked to actively connect to the specified local port instead of 906 doing a passive server-style listening. */ 907 arg++; 908 if(argc>arg) { 909 char *endptr; 910 unsigned long ulnum = strtoul(argv[arg], &endptr, 10); 911 if((endptr != argv[arg] + strlen(argv[arg])) || 912 (ulnum < 1025UL) || (ulnum > 65535UL)) { 913 fprintf(stderr, "sockfilt: invalid --connect argument (%s)\n", 914 argv[arg]); 915 return 0; 916 } 917 connectport = curlx_ultous(ulnum); 918 arg++; 919 } 920 } 921 else if(!strcmp("--addr", argv[arg])) { 922 /* Set an IP address to use with --connect; otherwise use localhost */ 923 arg++; 924 if(argc>arg) { 925 addr = argv[arg]; 926 arg++; 927 } 928 } 929 else { 930 puts("Usage: sockfilt [option]\n" 931 " --version\n" 932 " --verbose\n" 933 " --logfile [file]\n" 934 " --pidfile [file]\n" 935 " --ipv4\n" 936 " --ipv6\n" 937 " --bindonly\n" 938 " --port [port]\n" 939 " --connect [port]\n" 940 " --addr [address]"); 941 return 0; 942 } 943 } 944 945#ifdef WIN32 946 win32_init(); 947 atexit(win32_cleanup); 948#endif 949 950 install_signal_handlers(); 951 952#ifdef ENABLE_IPV6 953 if(!use_ipv6) 954#endif 955 sock = socket(AF_INET, SOCK_STREAM, 0); 956#ifdef ENABLE_IPV6 957 else 958 sock = socket(AF_INET6, SOCK_STREAM, 0); 959#endif 960 961 if(CURL_SOCKET_BAD == sock) { 962 error = SOCKERRNO; 963 logmsg("Error creating socket: (%d) %s", 964 error, strerror(error)); 965 write_stdout("FAIL\n", 5); 966 goto sockfilt_cleanup; 967 } 968 969 if(connectport) { 970 /* Active mode, we should connect to the given port number */ 971 mode = ACTIVE; 972#ifdef ENABLE_IPV6 973 if(!use_ipv6) { 974#endif 975 memset(&me.sa4, 0, sizeof(me.sa4)); 976 me.sa4.sin_family = AF_INET; 977 me.sa4.sin_port = htons(connectport); 978 me.sa4.sin_addr.s_addr = INADDR_ANY; 979 if (!addr) 980 addr = "127.0.0.1"; 981 Curl_inet_pton(AF_INET, addr, &me.sa4.sin_addr); 982 983 rc = connect(sock, &me.sa, sizeof(me.sa4)); 984#ifdef ENABLE_IPV6 985 } 986 else { 987 memset(&me.sa6, 0, sizeof(me.sa6)); 988 me.sa6.sin6_family = AF_INET6; 989 me.sa6.sin6_port = htons(connectport); 990 if (!addr) 991 addr = "::1"; 992 Curl_inet_pton(AF_INET6, addr, &me.sa6.sin6_addr); 993 994 rc = connect(sock, &me.sa, sizeof(me.sa6)); 995 } 996#endif /* ENABLE_IPV6 */ 997 if(rc) { 998 error = SOCKERRNO; 999 logmsg("Error connecting to port %hu: (%d) %s", 1000 connectport, error, strerror(error)); 1001 write_stdout("FAIL\n", 5); 1002 goto sockfilt_cleanup; 1003 } 1004 logmsg("====> Client connect"); 1005 msgsock = sock; /* use this as stream */ 1006 } 1007 else { 1008 /* passive daemon style */ 1009 sock = sockdaemon(sock, &port); 1010 if(CURL_SOCKET_BAD == sock) { 1011 write_stdout("FAIL\n", 5); 1012 goto sockfilt_cleanup; 1013 } 1014 msgsock = CURL_SOCKET_BAD; /* no stream socket yet */ 1015 } 1016 1017 logmsg("Running %s version", ipv_inuse); 1018 1019 if(connectport) 1020 logmsg("Connected to port %hu", connectport); 1021 else if(bind_only) 1022 logmsg("Bound without listening on port %hu", port); 1023 else 1024 logmsg("Listening on port %hu", port); 1025 1026 wrotepidfile = write_pidfile(pidname); 1027 if(!wrotepidfile) { 1028 write_stdout("FAIL\n", 5); 1029 goto sockfilt_cleanup; 1030 } 1031 1032 do { 1033 juggle_again = juggle(&msgsock, sock, &mode); 1034 } while(juggle_again); 1035 1036sockfilt_cleanup: 1037 1038 if((msgsock != sock) && (msgsock != CURL_SOCKET_BAD)) 1039 sclose(msgsock); 1040 1041 if(sock != CURL_SOCKET_BAD) 1042 sclose(sock); 1043 1044 if(wrotepidfile) 1045 unlink(pidname); 1046 1047 restore_signal_handlers(); 1048 1049 if(got_exit_signal) { 1050 logmsg("============> sockfilt exits with signal (%d)", exit_signal); 1051 /* 1052 * To properly set the return status of the process we 1053 * must raise the same signal SIGINT or SIGTERM that we 1054 * caught and let the old handler take care of it. 1055 */ 1056 raise(exit_signal); 1057 } 1058 1059 logmsg("============> sockfilt quits"); 1060 return 0; 1061} 1062 1063