1 /***************************************************************************
3 * Project ___| | | | _ \| |
5 * | (__| |_| | _ <| |___
6 * \___|\___/|_| \_\_____|
8 * Copyright (C) 1998 - 2014, Daniel Stenberg, <daniel@haxx.se>, et al.
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.
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.
18 * This software is distributed on an "AS IS" basis, WITHOUT WARRANTY OF ANY
19 * KIND, either express or implied.
21 ***************************************************************************/
22 #include "server_setup.h"
26 * 1. Accept a TCP connection on a custom port (ipv4 or ipv6), or connect
27 * to a given (localhost) port.
29 * 2. Get commands on STDIN. Pass data on to the TCP stream.
30 * Get data from TCP stream and pass on to STDOUT.
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:
37 * o We want the perl code to work with rather old perl installations, thus
38 * we cannot use recent perl modules or features.
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.
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.
47 * (Source originally based on sws.c)
51 * Signal handling notes for sockfilt
52 * ----------------------------------
54 * This program is a single-threaded process.
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.
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.
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.
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.
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!
86 #ifdef HAVE_NETINET_IN_H
87 #include <netinet/in.h>
89 #ifdef HAVE_ARPA_INET_H
90 #include <arpa/inet.h>
96 #define ENABLE_CURLX_PRINTF
97 /* make the curlx header define all printf() functions to use the curlx_*
99 #include "curlx.h" /* from the private lib dir */
101 #include "inet_pton.h"
103 #include "server_sockaddr.h"
104 #include "warnless.h"
106 /* include memdebug.h last */
107 #include "memdebug.h"
111 #define EINTR 4 /* errno.h value */
113 #define EAGAIN 11 /* errno.h value */
115 #define ENOMEM 12 /* errno.h value */
117 #define EINVAL 22 /* errno.h value */
120 #define DEFAULT_PORT 8999
122 #ifndef DEFAULT_LOGFILE
123 #define DEFAULT_LOGFILE "log/sockfilt.log"
126 const char *serverlogfile = DEFAULT_LOGFILE;
128 static bool verbose = FALSE;
129 static bool bind_only = FALSE;
131 static bool use_ipv6 = FALSE;
133 static const char *ipv_inuse = "IPv4";
134 static unsigned short port = DEFAULT_PORT;
135 static unsigned short connectport = 0; /* if non-zero, we activate this mode */
138 PASSIVE_LISTEN, /* as a server waiting for connections */
139 PASSIVE_CONNECT, /* as a server, connected to a client */
140 ACTIVE, /* as a client, connected to a server */
141 ACTIVE_DISCONNECT /* as a client, disconnected from server */
144 /* do-nothing macro replacement for systems which lack siginterrupt() */
146 #ifndef HAVE_SIGINTERRUPT
147 #define siginterrupt(x,y) do {} while(0)
150 /* vars used to keep around previous signal handlers */
152 typedef RETSIGTYPE (*SIGHANDLER_T)(int);
155 static SIGHANDLER_T old_sighup_handler = SIG_ERR;
159 static SIGHANDLER_T old_sigpipe_handler = SIG_ERR;
163 static SIGHANDLER_T old_sigalrm_handler = SIG_ERR;
167 static SIGHANDLER_T old_sigint_handler = SIG_ERR;
171 static SIGHANDLER_T old_sigterm_handler = SIG_ERR;
174 #if defined(SIGBREAK) && defined(WIN32)
175 static SIGHANDLER_T old_sigbreak_handler = SIG_ERR;
178 /* var which if set indicates that the program should finish execution */
180 SIG_ATOMIC_T got_exit_signal = 0;
182 /* if next is set indicates the first signal handled in exit_signal_handler */
184 static volatile int exit_signal = 0;
186 /* signal handler that will be triggered to indicate that the program
187 should finish its execution in a controlled manner as soon as possible.
188 The first time this is called it will set got_exit_signal to one and
189 store in exit_signal the signal that triggered its execution. */
191 static RETSIGTYPE exit_signal_handler(int signum)
193 int old_errno = errno;
194 if(got_exit_signal == 0) {
196 exit_signal = signum;
198 (void)signal(signum, exit_signal_handler);
202 static void install_signal_handlers(void)
205 /* ignore SIGHUP signal */
206 if((old_sighup_handler = signal(SIGHUP, SIG_IGN)) == SIG_ERR)
207 logmsg("cannot install SIGHUP handler: %s", strerror(errno));
210 /* ignore SIGPIPE signal */
211 if((old_sigpipe_handler = signal(SIGPIPE, SIG_IGN)) == SIG_ERR)
212 logmsg("cannot install SIGPIPE handler: %s", strerror(errno));
215 /* ignore SIGALRM signal */
216 if((old_sigalrm_handler = signal(SIGALRM, SIG_IGN)) == SIG_ERR)
217 logmsg("cannot install SIGALRM handler: %s", strerror(errno));
220 /* handle SIGINT signal with our exit_signal_handler */
221 if((old_sigint_handler = signal(SIGINT, exit_signal_handler)) == SIG_ERR)
222 logmsg("cannot install SIGINT handler: %s", strerror(errno));
224 siginterrupt(SIGINT, 1);
227 /* handle SIGTERM signal with our exit_signal_handler */
228 if((old_sigterm_handler = signal(SIGTERM, exit_signal_handler)) == SIG_ERR)
229 logmsg("cannot install SIGTERM handler: %s", strerror(errno));
231 siginterrupt(SIGTERM, 1);
233 #if defined(SIGBREAK) && defined(WIN32)
234 /* handle SIGBREAK signal with our exit_signal_handler */
235 if((old_sigbreak_handler = signal(SIGBREAK, exit_signal_handler)) == SIG_ERR)
236 logmsg("cannot install SIGBREAK handler: %s", strerror(errno));
238 siginterrupt(SIGBREAK, 1);
242 static void restore_signal_handlers(void)
245 if(SIG_ERR != old_sighup_handler)
246 (void)signal(SIGHUP, old_sighup_handler);
249 if(SIG_ERR != old_sigpipe_handler)
250 (void)signal(SIGPIPE, old_sigpipe_handler);
253 if(SIG_ERR != old_sigalrm_handler)
254 (void)signal(SIGALRM, old_sigalrm_handler);
257 if(SIG_ERR != old_sigint_handler)
258 (void)signal(SIGINT, old_sigint_handler);
261 if(SIG_ERR != old_sigterm_handler)
262 (void)signal(SIGTERM, old_sigterm_handler);
264 #if defined(SIGBREAK) && defined(WIN32)
265 if(SIG_ERR != old_sigbreak_handler)
266 (void)signal(SIGBREAK, old_sigbreak_handler);
272 * read-wrapper to support reading from stdin on Windows.
274 static ssize_t read_wincon(int fd, void *buf, size_t count)
276 HANDLE handle = NULL;
277 DWORD mode, rcount = 0;
280 if(fd == fileno(stdin)) {
281 handle = GetStdHandle(STD_INPUT_HANDLE);
284 return read(fd, buf, count);
287 if(GetConsoleMode(handle, &mode)) {
288 success = ReadConsole(handle, buf, count, &rcount, NULL);
291 success = ReadFile(handle, buf, count, &rcount, NULL);
297 errno = GetLastError();
301 #define read(a,b,c) read_wincon(a,b,c)
304 * write-wrapper to support writing to stdout and stderr on Windows.
306 static ssize_t write_wincon(int fd, const void *buf, size_t count)
308 HANDLE handle = NULL;
309 DWORD mode, wcount = 0;
312 if(fd == fileno(stdout)) {
313 handle = GetStdHandle(STD_OUTPUT_HANDLE);
315 else if(fd == fileno(stderr)) {
316 handle = GetStdHandle(STD_ERROR_HANDLE);
319 return write(fd, buf, count);
322 if(GetConsoleMode(handle, &mode)) {
323 success = WriteConsole(handle, buf, count, &wcount, NULL);
326 success = WriteFile(handle, buf, count, &wcount, NULL);
332 errno = GetLastError();
336 #define write(a,b,c) write_wincon(a,b,c)
340 * fullread is a wrapper around the read() function. This will repeat the call
341 * to read() until it actually has read the complete number of bytes indicated
342 * in nbytes or it fails with a condition that cannot be handled with a simple
343 * retry of the read call.
346 static ssize_t fullread(int filedes, void *buffer, size_t nbytes)
353 rc = read(filedes, (unsigned char *)buffer + nread, nbytes - nread);
355 if(got_exit_signal) {
356 logmsg("signalled to die");
362 if((error == EINTR) || (error == EAGAIN))
364 logmsg("reading from file descriptor: %d,", filedes);
365 logmsg("unrecoverable read() failure: (%d) %s",
366 error, strerror(error));
371 logmsg("got 0 reading from stdin");
377 } while((size_t)nread < nbytes);
380 logmsg("read %zd bytes", nread);
386 * fullwrite is a wrapper around the write() function. This will repeat the
387 * call to write() until it actually has written the complete number of bytes
388 * indicated in nbytes or it fails with a condition that cannot be handled
389 * with a simple retry of the write call.
392 static ssize_t fullwrite(int filedes, const void *buffer, size_t nbytes)
399 wc = write(filedes, (unsigned char *)buffer + nwrite, nbytes - nwrite);
401 if(got_exit_signal) {
402 logmsg("signalled to die");
408 if((error == EINTR) || (error == EAGAIN))
410 logmsg("writing to file descriptor: %d,", filedes);
411 logmsg("unrecoverable write() failure: (%d) %s",
412 error, strerror(error));
417 logmsg("put 0 writing to stdout");
423 } while((size_t)nwrite < nbytes);
426 logmsg("wrote %zd bytes", nwrite);
432 * read_stdin tries to read from stdin nbytes into the given buffer. This is a
433 * blocking function that will only return TRUE when nbytes have actually been
434 * read or FALSE when an unrecoverable error has been detected. Failure of this
435 * function is an indication that the sockfilt process should terminate.
438 static bool read_stdin(void *buffer, size_t nbytes)
440 ssize_t nread = fullread(fileno(stdin), buffer, nbytes);
441 if(nread != (ssize_t)nbytes) {
442 logmsg("exiting...");
449 * write_stdout tries to write to stdio nbytes from the given buffer. This is a
450 * blocking function that will only return TRUE when nbytes have actually been
451 * written or FALSE when an unrecoverable error has been detected. Failure of
452 * this function is an indication that the sockfilt process should terminate.
455 static bool write_stdout(const void *buffer, size_t nbytes)
457 ssize_t nwrite = fullwrite(fileno(stdout), buffer, nbytes);
458 if(nwrite != (ssize_t)nbytes) {
459 logmsg("exiting...");
465 static void lograw(unsigned char *buffer, ssize_t len)
469 unsigned char *ptr = buffer;
473 for(i=0; i<len; i++) {
476 sprintf(optr, "\\n");
481 sprintf(optr, "\\r");
486 sprintf(optr, "%c", (ISGRAPH(ptr[i]) || ptr[i]==0x20) ?ptr[i]:'.');
493 logmsg("'%s'", data);
499 logmsg("'%s'", data);
504 * WinSock select() does not support standard file descriptors,
505 * it can only check SOCKETs. The following function is an attempt
506 * to re-create a select() function with support for other handle types.
508 * select() function with support for WINSOCK2 sockets and all
509 * other handle types supported by WaitForMultipleObjectsEx().
511 * TODO: Differentiate between read/write/except for non-SOCKET handles.
513 * http://msdn.microsoft.com/en-us/library/windows/desktop/ms687028.aspx
514 * http://msdn.microsoft.com/en-us/library/windows/desktop/ms741572.aspx
516 static DWORD WINAPI select_ws_stdin_wait_thread(LPVOID lpParameter)
521 handle = (HANDLE) lpParameter;
523 if(GetConsoleMode(handle, &mode))
524 WaitForSingleObjectEx(handle, INFINITE, FALSE);
526 ReadFile(handle, NULL, 0, &mode, NULL);
530 static int select_ws(int nfds, fd_set *readfds, fd_set *writefds,
531 fd_set *exceptfds, struct timeval *timeout)
533 DWORD milliseconds, wait, idx;
534 WSAEVENT wsaevent, *wsaevents;
535 WSANETWORKEVENTS wsanetevents;
536 HANDLE handle, *handles;
537 curl_socket_t sock, *fdarr, *wsasocks;
540 DWORD nfd = 0, wsa = 0;
543 /* check if the input value is valid */
549 /* check if we got descriptors, sleep in case we got none */
551 Sleep((timeout->tv_sec * 1000) + (timeout->tv_usec / 1000));
555 /* allocate internal array for the original input handles */
556 fdarr = malloc(nfds * sizeof(curl_socket_t));
562 /* allocate internal array for the internal event handles */
563 handles = malloc(nfds * sizeof(HANDLE));
564 if(handles == NULL) {
569 /* allocate internal array for the internal socket handles */
570 wsasocks = malloc(nfds * sizeof(curl_socket_t));
571 if(wsasocks == NULL) {
576 /* allocate internal array for the internal WINSOCK2 events */
577 wsaevents = malloc(nfds * sizeof(WSAEVENT));
578 if(wsaevents == NULL) {
583 /* loop over the handles in the input descriptor sets */
584 for(fds = 0; fds < nfds; fds++) {
588 if(FD_ISSET(fds, readfds))
589 networkevents |= FD_READ|FD_ACCEPT|FD_CLOSE;
591 if(FD_ISSET(fds, writefds))
592 networkevents |= FD_WRITE|FD_CONNECT;
594 if(FD_ISSET(fds, exceptfds))
595 networkevents |= FD_OOB|FD_CLOSE;
597 /* only wait for events for which we actually care */
599 fdarr[nfd] = curlx_sitosk(fds);
600 if(fds == fileno(stdin)) {
601 handles[nfd] = CreateThread(NULL, 0,
602 &select_ws_stdin_wait_thread,
603 GetStdHandle(STD_INPUT_HANDLE),
606 else if(fds == fileno(stdout)) {
607 handles[nfd] = GetStdHandle(STD_OUTPUT_HANDLE);
609 else if(fds == fileno(stderr)) {
610 handles[nfd] = GetStdHandle(STD_ERROR_HANDLE);
613 wsaevent = WSACreateEvent();
614 if(wsaevent != WSA_INVALID_EVENT) {
615 error = WSAEventSelect(fds, wsaevent, networkevents);
616 if(error != SOCKET_ERROR) {
617 handles[nfd] = wsaevent;
618 wsasocks[wsa] = curlx_sitosk(fds);
619 wsaevents[wsa] = wsaevent;
623 handles[nfd] = (HANDLE) curlx_sitosk(fds);
624 WSACloseEvent(wsaevent);
632 /* convert struct timeval to milliseconds */
634 milliseconds = ((timeout->tv_sec * 1000) + (timeout->tv_usec / 1000));
637 milliseconds = INFINITE;
640 /* wait for one of the internal handles to trigger */
641 wait = WaitForMultipleObjectsEx(nfd, handles, FALSE, milliseconds, FALSE);
643 /* loop over the internal handles returned in the descriptors */
644 for(idx = 0; idx < nfd; idx++) {
645 handle = handles[idx];
647 fds = curlx_sktosi(sock);
649 /* check if the current internal handle was triggered */
650 if(wait != WAIT_FAILED && (wait - WAIT_OBJECT_0) <= idx &&
651 WaitForSingleObjectEx(handle, 0, FALSE) == WAIT_OBJECT_0) {
652 /* first handle stdin, stdout and stderr */
653 if(fds == fileno(stdin)) {
654 /* stdin is never ready for write or exceptional */
655 FD_CLR(sock, writefds);
656 FD_CLR(sock, exceptfds);
658 else if(fds == fileno(stdout) || fds == fileno(stderr)) {
659 /* stdout and stderr are never ready for read or exceptional */
660 FD_CLR(sock, readfds);
661 FD_CLR(sock, exceptfds);
664 /* try to handle the event with the WINSOCK2 functions */
665 error = WSAEnumNetworkEvents(fds, handle, &wsanetevents);
666 if(error != SOCKET_ERROR) {
667 /* remove from descriptor set if not ready for read/accept/close */
668 if(!(wsanetevents.lNetworkEvents & (FD_READ|FD_ACCEPT|FD_CLOSE)))
669 FD_CLR(sock, readfds);
671 /* remove from descriptor set if not ready for write/connect */
672 if(!(wsanetevents.lNetworkEvents & (FD_WRITE|FD_CONNECT)))
673 FD_CLR(sock, writefds);
676 * use exceptfds together with readfds to signal
677 * that the connection was closed by the client.
679 * Reason: FD_CLOSE is only signaled once, sometimes
680 * at the same time as FD_READ with data being available.
681 * This means that recv/sread is not reliable to detect
682 * that the connection is closed.
684 /* remove from descriptor set if not exceptional */
685 if(!(wsanetevents.lNetworkEvents & (FD_OOB|FD_CLOSE)))
686 FD_CLR(sock, exceptfds);
690 /* check if the event has not been filtered using specific tests */
691 if(FD_ISSET(sock, readfds) || FD_ISSET(sock, writefds) ||
692 FD_ISSET(sock, exceptfds)) {
697 /* remove from all descriptor sets since this handle did not trigger */
698 FD_CLR(sock, readfds);
699 FD_CLR(sock, writefds);
700 FD_CLR(sock, exceptfds);
704 for(idx = 0; idx < wsa; idx++) {
705 WSAEventSelect(wsasocks[idx], NULL, 0);
706 WSACloseEvent(wsaevents[idx]);
716 #define select(a,b,c,d,e) select_ws(a,b,c,d,e)
717 #endif /* USE_WINSOCK */
720 sockfdp is a pointer to an established stream or CURL_SOCKET_BAD
722 if sockfd is CURL_SOCKET_BAD, listendfd is a listening socket we must
725 static bool juggle(curl_socket_t *sockfdp,
726 curl_socket_t listenfd,
729 struct timeval timeout;
733 curl_socket_t sockfd = CURL_SOCKET_BAD;
736 ssize_t nread_socket;
737 ssize_t bytes_written;
741 /* 'buffer' is this excessively large only to be able to support things like
742 test 1003 which tests exceedingly large server response lines */
743 unsigned char buffer[17010];
746 if(got_exit_signal) {
747 logmsg("signalled to die, exiting...");
752 /* As a last resort, quit if sockfilt process becomes orphan. Just in case
753 parent ftpserver process has died without killing its sockfilt children */
755 logmsg("process becomes orphan, exiting");
760 timeout.tv_sec = 120;
767 FD_SET((curl_socket_t)fileno(stdin), &fds_read);
775 /* there's always a socket to wait for */
776 FD_SET(sockfd, &fds_read);
780 case PASSIVE_CONNECT:
783 if(CURL_SOCKET_BAD == sockfd) {
784 /* eeek, we are supposedly connected and then this cannot be -1 ! */
785 logmsg("socket is -1! on %s:%d", __FILE__, __LINE__);
786 maxfd = 0; /* stdin */
789 /* there's always a socket to wait for */
790 FD_SET(sockfd, &fds_read);
792 FD_SET(sockfd, &fds_err);
801 /* sockfd turns CURL_SOCKET_BAD when our connection has been closed */
802 if(CURL_SOCKET_BAD != sockfd) {
803 FD_SET(sockfd, &fds_read);
805 FD_SET(sockfd, &fds_err);
810 logmsg("No socket to read on");
815 case ACTIVE_DISCONNECT:
817 logmsg("disconnected, no socket to read on");
819 sockfd = CURL_SOCKET_BAD;
822 } /* switch(*mode) */
827 /* select() blocking behavior call on blocking descriptors please */
829 rc = select(maxfd + 1, &fds_read, &fds_write, &fds_err, &timeout);
831 if(got_exit_signal) {
832 logmsg("signalled to die, exiting...");
836 } while((rc == -1) && ((error = errno) == EINTR));
839 logmsg("select() failed with error: (%d) %s",
840 error, strerror(error));
849 if(FD_ISSET(fileno(stdin), &fds_read)) {
850 /* read from stdin, commands/data to be dealt with and possibly passed on
855 4 letter command + LF [mandatory]
857 4-digit hexadecimal data length + LF [if the command takes data]
858 data [the data being as long as set above]
862 DATA - plain pass-thru data
865 if(!read_stdin(buffer, 5))
868 logmsg("Received %c%c%c%c (on stdin)",
869 buffer[0], buffer[1], buffer[2], buffer[3] );
871 if(!memcmp("PING", buffer, 4)) {
872 /* send reply on stdout, just proving we are alive */
873 if(!write_stdout("PONG\n", 5))
877 else if(!memcmp("PORT", buffer, 4)) {
878 /* Question asking us what PORT number we are listening to.
879 Replies to PORT with "IPv[num]/[port]" */
880 sprintf((char *)buffer, "%s/%hu\n", ipv_inuse, port);
881 buffer_len = (ssize_t)strlen((char *)buffer);
882 snprintf(data, sizeof(data), "PORT\n%04zx\n", buffer_len);
883 if(!write_stdout(data, 10))
885 if(!write_stdout(buffer, buffer_len))
888 else if(!memcmp("QUIT", buffer, 4)) {
893 else if(!memcmp("DATA", buffer, 4)) {
894 /* data IN => data OUT */
896 if(!read_stdin(buffer, 5))
901 buffer_len = (ssize_t)strtol((char *)buffer, NULL, 16);
902 if (buffer_len > (ssize_t)sizeof(buffer)) {
903 logmsg("ERROR: Buffer size (%zu bytes) too small for data size "
904 "(%zd bytes)", sizeof(buffer), buffer_len);
907 logmsg("> %zd bytes data, server => client", buffer_len);
909 if(!read_stdin(buffer, buffer_len))
912 lograw(buffer, buffer_len);
914 if(*mode == PASSIVE_LISTEN) {
915 logmsg("*** We are disconnected!");
916 if(!write_stdout("DISC\n", 5))
920 /* send away on the socket */
921 bytes_written = swrite(sockfd, buffer, buffer_len);
922 if(bytes_written != buffer_len) {
923 logmsg("Not all data was sent. Bytes to send: %zd sent: %zd",
924 buffer_len, bytes_written);
928 else if(!memcmp("DISC", buffer, 4)) {
930 if(!write_stdout("DISC\n", 5))
932 if(sockfd != CURL_SOCKET_BAD) {
933 logmsg("====> Client forcibly disconnected");
935 *sockfdp = CURL_SOCKET_BAD;
936 if(*mode == PASSIVE_CONNECT)
937 *mode = PASSIVE_LISTEN;
939 *mode = ACTIVE_DISCONNECT;
942 logmsg("attempt to close already dead connection");
948 if((sockfd != CURL_SOCKET_BAD) && (FD_ISSET(sockfd, &fds_read)) ) {
950 curl_socket_t newfd = CURL_SOCKET_BAD; /* newly accepted socket */
952 if(*mode == PASSIVE_LISTEN) {
953 /* there's no stream set up yet, this is an indication that there's a
954 client connecting. */
955 newfd = accept(sockfd, NULL, NULL);
956 if(CURL_SOCKET_BAD == newfd) {
958 logmsg("accept(%d, NULL, NULL) failed with error: (%d) %s",
959 sockfd, error, strerror(error));
962 logmsg("====> Client connect");
963 if(!write_stdout("CNCT\n", 5))
965 *sockfdp = newfd; /* store the new socket */
966 *mode = PASSIVE_CONNECT; /* we have connected */
971 /* read from socket, pass on data to stdout */
972 nread_socket = sread(sockfd, buffer, sizeof(buffer));
974 if(nread_socket > 0) {
975 snprintf(data, sizeof(data), "DATA\n%04zx\n", nread_socket);
976 if(!write_stdout(data, 10))
978 if(!write_stdout(buffer, nread_socket))
981 logmsg("< %zd bytes data, client => server", nread_socket);
982 lograw(buffer, nread_socket);
987 || FD_ISSET(sockfd, &fds_err)
990 logmsg("====> Client disconnect");
991 if(!write_stdout("DISC\n", 5))
994 *sockfdp = CURL_SOCKET_BAD;
995 if(*mode == PASSIVE_CONNECT)
996 *mode = PASSIVE_LISTEN;
998 *mode = ACTIVE_DISCONNECT;
1006 static curl_socket_t sockdaemon(curl_socket_t sock,
1007 unsigned short *listenport)
1009 /* passive daemon style */
1010 srvr_sockaddr_union_t listener;
1022 rc = setsockopt(sock, SOL_SOCKET, SO_REUSEADDR,
1023 (void *)&flag, sizeof(flag));
1026 logmsg("setsockopt(SO_REUSEADDR) failed with error: (%d) %s",
1027 error, strerror(error));
1029 rc = wait_ms(delay);
1031 /* should not happen */
1033 logmsg("wait_ms() failed with error: (%d) %s",
1034 error, strerror(error));
1036 return CURL_SOCKET_BAD;
1038 if(got_exit_signal) {
1039 logmsg("signalled to die, exiting...");
1041 return CURL_SOCKET_BAD;
1044 delay *= 2; /* double the sleep for next attempt */
1047 } while(rc && maxretr--);
1050 logmsg("setsockopt(SO_REUSEADDR) failed %d times in %d ms. Error: (%d) %s",
1051 attempt, totdelay, error, strerror(error));
1052 logmsg("Continuing anyway...");
1055 /* When the specified listener port is zero, it is actually a
1056 request to let the system choose a non-zero available port. */
1061 memset(&listener.sa4, 0, sizeof(listener.sa4));
1062 listener.sa4.sin_family = AF_INET;
1063 listener.sa4.sin_addr.s_addr = INADDR_ANY;
1064 listener.sa4.sin_port = htons(*listenport);
1065 rc = bind(sock, &listener.sa, sizeof(listener.sa4));
1069 memset(&listener.sa6, 0, sizeof(listener.sa6));
1070 listener.sa6.sin6_family = AF_INET6;
1071 listener.sa6.sin6_addr = in6addr_any;
1072 listener.sa6.sin6_port = htons(*listenport);
1073 rc = bind(sock, &listener.sa, sizeof(listener.sa6));
1075 #endif /* ENABLE_IPV6 */
1078 logmsg("Error binding socket on port %hu: (%d) %s",
1079 *listenport, error, strerror(error));
1081 return CURL_SOCKET_BAD;
1085 /* The system was supposed to choose a port number, figure out which
1086 port we actually got and update the listener port value with it. */
1087 curl_socklen_t la_size;
1088 srvr_sockaddr_union_t localaddr;
1092 la_size = sizeof(localaddr.sa4);
1095 la_size = sizeof(localaddr.sa6);
1097 memset(&localaddr.sa, 0, (size_t)la_size);
1098 if(getsockname(sock, &localaddr.sa, &la_size) < 0) {
1100 logmsg("getsockname() failed with error: (%d) %s",
1101 error, strerror(error));
1103 return CURL_SOCKET_BAD;
1105 switch (localaddr.sa.sa_family) {
1107 *listenport = ntohs(localaddr.sa4.sin_port);
1111 *listenport = ntohs(localaddr.sa6.sin6_port);
1118 /* Real failure, listener port shall not be zero beyond this point. */
1119 logmsg("Apparently getsockname() succeeded, with listener port zero.");
1120 logmsg("A valid reason for this failure is a binary built without");
1121 logmsg("proper network library linkage. This might not be the only");
1122 logmsg("reason, but double check it before anything else.");
1124 return CURL_SOCKET_BAD;
1128 /* bindonly option forces no listening */
1130 logmsg("instructed to bind port without listening");
1134 /* start accepting connections */
1135 rc = listen(sock, 5);
1138 logmsg("listen(%d, 5) failed with error: (%d) %s",
1139 sock, error, strerror(error));
1141 return CURL_SOCKET_BAD;
1148 int main(int argc, char *argv[])
1150 srvr_sockaddr_union_t me;
1151 curl_socket_t sock = CURL_SOCKET_BAD;
1152 curl_socket_t msgsock = CURL_SOCKET_BAD;
1153 int wrotepidfile = 0;
1154 char *pidname= (char *)".sockfilt.pid";
1159 enum sockmode mode = PASSIVE_LISTEN; /* default */
1160 const char *addr = NULL;
1163 if(!strcmp("--version", argv[arg])) {
1164 printf("sockfilt IPv4%s\n",
1173 else if(!strcmp("--verbose", argv[arg])) {
1177 else if(!strcmp("--pidfile", argv[arg])) {
1180 pidname = argv[arg++];
1182 else if(!strcmp("--logfile", argv[arg])) {
1185 serverlogfile = argv[arg++];
1187 else if(!strcmp("--ipv6", argv[arg])) {
1194 else if(!strcmp("--ipv4", argv[arg])) {
1195 /* for completeness, we support this option as well */
1202 else if(!strcmp("--bindonly", argv[arg])) {
1206 else if(!strcmp("--port", argv[arg])) {
1210 unsigned long ulnum = strtoul(argv[arg], &endptr, 10);
1211 if((endptr != argv[arg] + strlen(argv[arg])) ||
1212 ((ulnum != 0UL) && ((ulnum < 1025UL) || (ulnum > 65535UL)))) {
1213 fprintf(stderr, "sockfilt: invalid --port argument (%s)\n",
1217 port = curlx_ultous(ulnum);
1221 else if(!strcmp("--connect", argv[arg])) {
1222 /* Asked to actively connect to the specified local port instead of
1223 doing a passive server-style listening. */
1227 unsigned long ulnum = strtoul(argv[arg], &endptr, 10);
1228 if((endptr != argv[arg] + strlen(argv[arg])) ||
1229 (ulnum < 1025UL) || (ulnum > 65535UL)) {
1230 fprintf(stderr, "sockfilt: invalid --connect argument (%s)\n",
1234 connectport = curlx_ultous(ulnum);
1238 else if(!strcmp("--addr", argv[arg])) {
1239 /* Set an IP address to use with --connect; otherwise use localhost */
1247 puts("Usage: sockfilt [option]\n"
1250 " --logfile [file]\n"
1251 " --pidfile [file]\n"
1256 " --connect [port]\n"
1257 " --addr [address]");
1264 atexit(win32_cleanup);
1266 setmode(fileno(stdin), O_BINARY);
1267 setmode(fileno(stdout), O_BINARY);
1268 setmode(fileno(stderr), O_BINARY);
1271 install_signal_handlers();
1276 sock = socket(AF_INET, SOCK_STREAM, 0);
1279 sock = socket(AF_INET6, SOCK_STREAM, 0);
1282 if(CURL_SOCKET_BAD == sock) {
1284 logmsg("Error creating socket: (%d) %s",
1285 error, strerror(error));
1286 write_stdout("FAIL\n", 5);
1287 goto sockfilt_cleanup;
1291 /* Active mode, we should connect to the given port number */
1296 memset(&me.sa4, 0, sizeof(me.sa4));
1297 me.sa4.sin_family = AF_INET;
1298 me.sa4.sin_port = htons(connectport);
1299 me.sa4.sin_addr.s_addr = INADDR_ANY;
1302 Curl_inet_pton(AF_INET, addr, &me.sa4.sin_addr);
1304 rc = connect(sock, &me.sa, sizeof(me.sa4));
1308 memset(&me.sa6, 0, sizeof(me.sa6));
1309 me.sa6.sin6_family = AF_INET6;
1310 me.sa6.sin6_port = htons(connectport);
1313 Curl_inet_pton(AF_INET6, addr, &me.sa6.sin6_addr);
1315 rc = connect(sock, &me.sa, sizeof(me.sa6));
1317 #endif /* ENABLE_IPV6 */
1320 logmsg("Error connecting to port %hu: (%d) %s",
1321 connectport, error, strerror(error));
1322 write_stdout("FAIL\n", 5);
1323 goto sockfilt_cleanup;
1325 logmsg("====> Client connect");
1326 msgsock = sock; /* use this as stream */
1329 /* passive daemon style */
1330 sock = sockdaemon(sock, &port);
1331 if(CURL_SOCKET_BAD == sock) {
1332 write_stdout("FAIL\n", 5);
1333 goto sockfilt_cleanup;
1335 msgsock = CURL_SOCKET_BAD; /* no stream socket yet */
1338 logmsg("Running %s version", ipv_inuse);
1341 logmsg("Connected to port %hu", connectport);
1343 logmsg("Bound without listening on port %hu", port);
1345 logmsg("Listening on port %hu", port);
1347 wrotepidfile = write_pidfile(pidname);
1349 write_stdout("FAIL\n", 5);
1350 goto sockfilt_cleanup;
1354 juggle_again = juggle(&msgsock, sock, &mode);
1355 } while(juggle_again);
1359 if((msgsock != sock) && (msgsock != CURL_SOCKET_BAD))
1362 if(sock != CURL_SOCKET_BAD)
1368 restore_signal_handlers();
1370 if(got_exit_signal) {
1371 logmsg("============> sockfilt exits with signal (%d)", exit_signal);
1373 * To properly set the return status of the process we
1374 * must raise the same signal SIGINT or SIGTERM that we
1375 * caught and let the old handler take care of it.
1380 logmsg("============> sockfilt quits");