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();
300 #define read(a,b,c) read_wincon(a,b,c)
303 * write-wrapper to support writing to stdout and stderr on Windows.
305 static ssize_t write_wincon(int fd, const void *buf, size_t count)
307 HANDLE handle = NULL;
308 DWORD mode, wcount = 0;
311 if(fd == fileno(stdout)) {
312 handle = GetStdHandle(STD_OUTPUT_HANDLE);
314 else if(fd == fileno(stderr)) {
315 handle = GetStdHandle(STD_ERROR_HANDLE);
318 return write(fd, buf, count);
321 if(GetConsoleMode(handle, &mode)) {
322 success = WriteConsole(handle, buf, count, &wcount, NULL);
325 success = WriteFile(handle, buf, count, &wcount, NULL);
331 errno = GetLastError();
334 #define write(a,b,c) write_wincon(a,b,c)
338 * fullread is a wrapper around the read() function. This will repeat the call
339 * to read() until it actually has read the complete number of bytes indicated
340 * in nbytes or it fails with a condition that cannot be handled with a simple
341 * retry of the read call.
344 static ssize_t fullread(int filedes, void *buffer, size_t nbytes)
351 rc = read(filedes, (unsigned char *)buffer + nread, nbytes - nread);
353 if(got_exit_signal) {
354 logmsg("signalled to die");
360 if((error == EINTR) || (error == EAGAIN))
362 logmsg("reading from file descriptor: %d,", filedes);
363 logmsg("unrecoverable read() failure: (%d) %s",
364 error, strerror(error));
369 logmsg("got 0 reading from stdin");
375 } while((size_t)nread < nbytes);
378 logmsg("read %zd bytes", nread);
384 * fullwrite is a wrapper around the write() function. This will repeat the
385 * call to write() until it actually has written the complete number of bytes
386 * indicated in nbytes or it fails with a condition that cannot be handled
387 * with a simple retry of the write call.
390 static ssize_t fullwrite(int filedes, const void *buffer, size_t nbytes)
397 wc = write(filedes, (unsigned char *)buffer + nwrite, nbytes - nwrite);
399 if(got_exit_signal) {
400 logmsg("signalled to die");
406 if((error == EINTR) || (error == EAGAIN))
408 logmsg("writing to file descriptor: %d,", filedes);
409 logmsg("unrecoverable write() failure: (%d) %s",
410 error, strerror(error));
415 logmsg("put 0 writing to stdout");
421 } while((size_t)nwrite < nbytes);
424 logmsg("wrote %zd bytes", nwrite);
430 * read_stdin tries to read from stdin nbytes into the given buffer. This is a
431 * blocking function that will only return TRUE when nbytes have actually been
432 * read or FALSE when an unrecoverable error has been detected. Failure of this
433 * function is an indication that the sockfilt process should terminate.
436 static bool read_stdin(void *buffer, size_t nbytes)
438 ssize_t nread = fullread(fileno(stdin), buffer, nbytes);
439 if(nread != (ssize_t)nbytes) {
440 logmsg("exiting...");
447 * write_stdout tries to write to stdio nbytes from the given buffer. This is a
448 * blocking function that will only return TRUE when nbytes have actually been
449 * written or FALSE when an unrecoverable error has been detected. Failure of
450 * this function is an indication that the sockfilt process should terminate.
453 static bool write_stdout(const void *buffer, size_t nbytes)
455 ssize_t nwrite = fullwrite(fileno(stdout), buffer, nbytes);
456 if(nwrite != (ssize_t)nbytes) {
457 logmsg("exiting...");
463 static void lograw(unsigned char *buffer, ssize_t len)
467 unsigned char *ptr = buffer;
471 for(i=0; i<len; i++) {
474 sprintf(optr, "\\n");
479 sprintf(optr, "\\r");
484 sprintf(optr, "%c", (ISGRAPH(ptr[i]) || ptr[i]==0x20) ?ptr[i]:'.');
491 logmsg("'%s'", data);
497 logmsg("'%s'", data);
502 * WinSock select() does not support standard file descriptors,
503 * it can only check SOCKETs. The following function is an attempt
504 * to re-create a select() function with support for other handle types.
506 * select() function with support for WINSOCK2 sockets and all
507 * other handle types supported by WaitForMultipleObjectsEx().
509 * TODO: Differentiate between read/write/except for non-SOCKET handles.
511 * http://msdn.microsoft.com/en-us/library/windows/desktop/ms687028.aspx
512 * http://msdn.microsoft.com/en-us/library/windows/desktop/ms741572.aspx
514 static DWORD WINAPI select_ws_stdin_wait_thread(LPVOID lpParameter)
519 handle = (HANDLE) lpParameter;
521 if(GetConsoleMode(handle, &mode))
522 WaitForSingleObjectEx(handle, INFINITE, FALSE);
524 ReadFile(handle, NULL, 0, &mode, NULL);
528 static int select_ws(int nfds, fd_set *readfds, fd_set *writefds,
529 fd_set *exceptfds, struct timeval *timeout)
531 DWORD milliseconds, wait, idx;
532 WSAEVENT wsaevent, *wsaevents;
533 WSANETWORKEVENTS wsanetevents;
534 HANDLE handle, *handles;
535 curl_socket_t sock, *fdarr, *wsasocks;
538 DWORD nfd = 0, wsa = 0;
541 /* check if the input value is valid */
547 /* check if we got descriptors, sleep in case we got none */
549 Sleep((timeout->tv_sec * 1000) + (timeout->tv_usec / 1000));
553 /* allocate internal array for the original input handles */
554 fdarr = malloc(nfds * sizeof(curl_socket_t));
560 /* allocate internal array for the internal event handles */
561 handles = malloc(nfds * sizeof(HANDLE));
562 if(handles == NULL) {
567 /* allocate internal array for the internal socket handles */
568 wsasocks = malloc(nfds * sizeof(curl_socket_t));
569 if(wsasocks == NULL) {
574 /* allocate internal array for the internal WINSOCK2 events */
575 wsaevents = malloc(nfds * sizeof(WSAEVENT));
576 if(wsaevents == NULL) {
581 /* loop over the handles in the input descriptor sets */
582 for(fds = 0; fds < nfds; fds++) {
586 if(FD_ISSET(fds, readfds))
587 networkevents |= FD_READ|FD_ACCEPT|FD_CLOSE;
589 if(FD_ISSET(fds, writefds))
590 networkevents |= FD_WRITE|FD_CONNECT;
592 if(FD_ISSET(fds, exceptfds))
593 networkevents |= FD_OOB|FD_CLOSE;
595 /* only wait for events for which we actually care */
597 fdarr[nfd] = curlx_sitosk(fds);
598 if(fds == fileno(stdin)) {
599 handles[nfd] = CreateThread(NULL, 0,
600 &select_ws_stdin_wait_thread,
601 GetStdHandle(STD_INPUT_HANDLE),
604 else if(fds == fileno(stdout)) {
605 handles[nfd] = GetStdHandle(STD_OUTPUT_HANDLE);
607 else if(fds == fileno(stderr)) {
608 handles[nfd] = GetStdHandle(STD_ERROR_HANDLE);
611 wsaevent = WSACreateEvent();
612 if(wsaevent != WSA_INVALID_EVENT) {
613 error = WSAEventSelect(fds, wsaevent, networkevents);
614 if(error != SOCKET_ERROR) {
615 handles[nfd] = wsaevent;
616 wsasocks[wsa] = curlx_sitosk(fds);
617 wsaevents[wsa] = wsaevent;
621 handles[nfd] = (HANDLE) curlx_sitosk(fds);
622 WSACloseEvent(wsaevent);
630 /* convert struct timeval to milliseconds */
632 milliseconds = ((timeout->tv_sec * 1000) + (timeout->tv_usec / 1000));
635 milliseconds = INFINITE;
638 /* wait for one of the internal handles to trigger */
639 wait = WaitForMultipleObjectsEx(nfd, handles, FALSE, milliseconds, FALSE);
641 /* loop over the internal handles returned in the descriptors */
642 for(idx = 0; idx < nfd; idx++) {
643 handle = handles[idx];
645 fds = curlx_sktosi(sock);
647 /* check if the current internal handle was triggered */
648 if(wait != WAIT_FAILED && (wait - WAIT_OBJECT_0) <= idx &&
649 WaitForSingleObjectEx(handle, 0, FALSE) == WAIT_OBJECT_0) {
650 /* first handle stdin, stdout and stderr */
651 if(fds == fileno(stdin)) {
652 /* stdin is never ready for write or exceptional */
653 FD_CLR(sock, writefds);
654 FD_CLR(sock, exceptfds);
656 else if(fds == fileno(stdout) || fds == fileno(stderr)) {
657 /* stdout and stderr are never ready for read or exceptional */
658 FD_CLR(sock, readfds);
659 FD_CLR(sock, exceptfds);
662 /* try to handle the event with the WINSOCK2 functions */
663 error = WSAEnumNetworkEvents(fds, handle, &wsanetevents);
664 if(error != SOCKET_ERROR) {
665 /* remove from descriptor set if not ready for read/accept/close */
666 if(!(wsanetevents.lNetworkEvents & (FD_READ|FD_ACCEPT|FD_CLOSE)))
667 FD_CLR(sock, readfds);
669 /* remove from descriptor set if not ready for write/connect */
670 if(!(wsanetevents.lNetworkEvents & (FD_WRITE|FD_CONNECT)))
671 FD_CLR(sock, writefds);
674 * use exceptfds together with readfds to signal
675 * that the connection was closed by the client.
677 * Reason: FD_CLOSE is only signaled once, sometimes
678 * at the same time as FD_READ with data being available.
679 * This means that recv/sread is not reliable to detect
680 * that the connection is closed.
682 /* remove from descriptor set if not exceptional */
683 if(!(wsanetevents.lNetworkEvents & (FD_OOB|FD_CLOSE)))
684 FD_CLR(sock, exceptfds);
688 /* check if the event has not been filtered using specific tests */
689 if(FD_ISSET(sock, readfds) || FD_ISSET(sock, writefds) ||
690 FD_ISSET(sock, exceptfds)) {
695 /* remove from all descriptor sets since this handle did not trigger */
696 FD_CLR(sock, readfds);
697 FD_CLR(sock, writefds);
698 FD_CLR(sock, exceptfds);
702 for(idx = 0; idx < wsa; idx++) {
703 WSAEventSelect(wsasocks[idx], NULL, 0);
704 WSACloseEvent(wsaevents[idx]);
714 #define select(a,b,c,d,e) select_ws(a,b,c,d,e)
715 #endif /* USE_WINSOCK */
718 sockfdp is a pointer to an established stream or CURL_SOCKET_BAD
720 if sockfd is CURL_SOCKET_BAD, listendfd is a listening socket we must
723 static bool juggle(curl_socket_t *sockfdp,
724 curl_socket_t listenfd,
727 struct timeval timeout;
731 curl_socket_t sockfd = CURL_SOCKET_BAD;
734 ssize_t nread_socket;
735 ssize_t bytes_written;
739 /* 'buffer' is this excessively large only to be able to support things like
740 test 1003 which tests exceedingly large server response lines */
741 unsigned char buffer[17010];
744 if(got_exit_signal) {
745 logmsg("signalled to die, exiting...");
750 /* As a last resort, quit if sockfilt process becomes orphan. Just in case
751 parent ftpserver process has died without killing its sockfilt children */
753 logmsg("process becomes orphan, exiting");
758 timeout.tv_sec = 120;
765 FD_SET((curl_socket_t)fileno(stdin), &fds_read);
773 /* there's always a socket to wait for */
774 FD_SET(sockfd, &fds_read);
778 case PASSIVE_CONNECT:
781 if(CURL_SOCKET_BAD == sockfd) {
782 /* eeek, we are supposedly connected and then this cannot be -1 ! */
783 logmsg("socket is -1! on %s:%d", __FILE__, __LINE__);
784 maxfd = 0; /* stdin */
787 /* there's always a socket to wait for */
788 FD_SET(sockfd, &fds_read);
790 FD_SET(sockfd, &fds_err);
799 /* sockfd turns CURL_SOCKET_BAD when our connection has been closed */
800 if(CURL_SOCKET_BAD != sockfd) {
801 FD_SET(sockfd, &fds_read);
803 FD_SET(sockfd, &fds_err);
808 logmsg("No socket to read on");
813 case ACTIVE_DISCONNECT:
815 logmsg("disconnected, no socket to read on");
817 sockfd = CURL_SOCKET_BAD;
820 } /* switch(*mode) */
825 /* select() blocking behavior call on blocking descriptors please */
827 rc = select(maxfd + 1, &fds_read, &fds_write, &fds_err, &timeout);
829 if(got_exit_signal) {
830 logmsg("signalled to die, exiting...");
834 } while((rc == -1) && ((error = errno) == EINTR));
837 logmsg("select() failed with error: (%d) %s",
838 error, strerror(error));
847 if(FD_ISSET(fileno(stdin), &fds_read)) {
848 /* read from stdin, commands/data to be dealt with and possibly passed on
853 4 letter command + LF [mandatory]
855 4-digit hexadecimal data length + LF [if the command takes data]
856 data [the data being as long as set above]
860 DATA - plain pass-thru data
863 if(!read_stdin(buffer, 5))
866 logmsg("Received %c%c%c%c (on stdin)",
867 buffer[0], buffer[1], buffer[2], buffer[3] );
869 if(!memcmp("PING", buffer, 4)) {
870 /* send reply on stdout, just proving we are alive */
871 if(!write_stdout("PONG\n", 5))
875 else if(!memcmp("PORT", buffer, 4)) {
876 /* Question asking us what PORT number we are listening to.
877 Replies to PORT with "IPv[num]/[port]" */
878 sprintf((char *)buffer, "%s/%hu\n", ipv_inuse, port);
879 buffer_len = (ssize_t)strlen((char *)buffer);
880 snprintf(data, sizeof(data), "PORT\n%04zx\n", buffer_len);
881 if(!write_stdout(data, 10))
883 if(!write_stdout(buffer, buffer_len))
886 else if(!memcmp("QUIT", buffer, 4)) {
891 else if(!memcmp("DATA", buffer, 4)) {
892 /* data IN => data OUT */
894 if(!read_stdin(buffer, 5))
899 buffer_len = (ssize_t)strtol((char *)buffer, NULL, 16);
900 if (buffer_len > (ssize_t)sizeof(buffer)) {
901 logmsg("ERROR: Buffer size (%zu bytes) too small for data size "
902 "(%zd bytes)", sizeof(buffer), buffer_len);
905 logmsg("> %zd bytes data, server => client", buffer_len);
907 if(!read_stdin(buffer, buffer_len))
910 lograw(buffer, buffer_len);
912 if(*mode == PASSIVE_LISTEN) {
913 logmsg("*** We are disconnected!");
914 if(!write_stdout("DISC\n", 5))
918 /* send away on the socket */
919 bytes_written = swrite(sockfd, buffer, buffer_len);
920 if(bytes_written != buffer_len) {
921 logmsg("Not all data was sent. Bytes to send: %zd sent: %zd",
922 buffer_len, bytes_written);
926 else if(!memcmp("DISC", buffer, 4)) {
928 if(!write_stdout("DISC\n", 5))
930 if(sockfd != CURL_SOCKET_BAD) {
931 logmsg("====> Client forcibly disconnected");
933 *sockfdp = CURL_SOCKET_BAD;
934 if(*mode == PASSIVE_CONNECT)
935 *mode = PASSIVE_LISTEN;
937 *mode = ACTIVE_DISCONNECT;
940 logmsg("attempt to close already dead connection");
946 if((sockfd != CURL_SOCKET_BAD) && (FD_ISSET(sockfd, &fds_read)) ) {
948 curl_socket_t newfd = CURL_SOCKET_BAD; /* newly accepted socket */
950 if(*mode == PASSIVE_LISTEN) {
951 /* there's no stream set up yet, this is an indication that there's a
952 client connecting. */
953 newfd = accept(sockfd, NULL, NULL);
954 if(CURL_SOCKET_BAD == newfd) {
956 logmsg("accept(%d, NULL, NULL) failed with error: (%d) %s",
957 sockfd, error, strerror(error));
960 logmsg("====> Client connect");
961 if(!write_stdout("CNCT\n", 5))
963 *sockfdp = newfd; /* store the new socket */
964 *mode = PASSIVE_CONNECT; /* we have connected */
969 /* read from socket, pass on data to stdout */
970 nread_socket = sread(sockfd, buffer, sizeof(buffer));
972 if(nread_socket > 0) {
973 snprintf(data, sizeof(data), "DATA\n%04zx\n", nread_socket);
974 if(!write_stdout(data, 10))
976 if(!write_stdout(buffer, nread_socket))
979 logmsg("< %zd bytes data, client => server", nread_socket);
980 lograw(buffer, nread_socket);
985 || FD_ISSET(sockfd, &fds_err)
988 logmsg("====> Client disconnect");
989 if(!write_stdout("DISC\n", 5))
992 *sockfdp = CURL_SOCKET_BAD;
993 if(*mode == PASSIVE_CONNECT)
994 *mode = PASSIVE_LISTEN;
996 *mode = ACTIVE_DISCONNECT;
1004 static curl_socket_t sockdaemon(curl_socket_t sock,
1005 unsigned short *listenport)
1007 /* passive daemon style */
1008 srvr_sockaddr_union_t listener;
1020 rc = setsockopt(sock, SOL_SOCKET, SO_REUSEADDR,
1021 (void *)&flag, sizeof(flag));
1024 logmsg("setsockopt(SO_REUSEADDR) failed with error: (%d) %s",
1025 error, strerror(error));
1027 rc = wait_ms(delay);
1029 /* should not happen */
1031 logmsg("wait_ms() failed with error: (%d) %s",
1032 error, strerror(error));
1034 return CURL_SOCKET_BAD;
1036 if(got_exit_signal) {
1037 logmsg("signalled to die, exiting...");
1039 return CURL_SOCKET_BAD;
1042 delay *= 2; /* double the sleep for next attempt */
1045 } while(rc && maxretr--);
1048 logmsg("setsockopt(SO_REUSEADDR) failed %d times in %d ms. Error: (%d) %s",
1049 attempt, totdelay, error, strerror(error));
1050 logmsg("Continuing anyway...");
1053 /* When the specified listener port is zero, it is actually a
1054 request to let the system choose a non-zero available port. */
1059 memset(&listener.sa4, 0, sizeof(listener.sa4));
1060 listener.sa4.sin_family = AF_INET;
1061 listener.sa4.sin_addr.s_addr = INADDR_ANY;
1062 listener.sa4.sin_port = htons(*listenport);
1063 rc = bind(sock, &listener.sa, sizeof(listener.sa4));
1067 memset(&listener.sa6, 0, sizeof(listener.sa6));
1068 listener.sa6.sin6_family = AF_INET6;
1069 listener.sa6.sin6_addr = in6addr_any;
1070 listener.sa6.sin6_port = htons(*listenport);
1071 rc = bind(sock, &listener.sa, sizeof(listener.sa6));
1073 #endif /* ENABLE_IPV6 */
1076 logmsg("Error binding socket on port %hu: (%d) %s",
1077 *listenport, error, strerror(error));
1079 return CURL_SOCKET_BAD;
1083 /* The system was supposed to choose a port number, figure out which
1084 port we actually got and update the listener port value with it. */
1085 curl_socklen_t la_size;
1086 srvr_sockaddr_union_t localaddr;
1090 la_size = sizeof(localaddr.sa4);
1093 la_size = sizeof(localaddr.sa6);
1095 memset(&localaddr.sa, 0, (size_t)la_size);
1096 if(getsockname(sock, &localaddr.sa, &la_size) < 0) {
1098 logmsg("getsockname() failed with error: (%d) %s",
1099 error, strerror(error));
1101 return CURL_SOCKET_BAD;
1103 switch (localaddr.sa.sa_family) {
1105 *listenport = ntohs(localaddr.sa4.sin_port);
1109 *listenport = ntohs(localaddr.sa6.sin6_port);
1116 /* Real failure, listener port shall not be zero beyond this point. */
1117 logmsg("Apparently getsockname() succeeded, with listener port zero.");
1118 logmsg("A valid reason for this failure is a binary built without");
1119 logmsg("proper network library linkage. This might not be the only");
1120 logmsg("reason, but double check it before anything else.");
1122 return CURL_SOCKET_BAD;
1126 /* bindonly option forces no listening */
1128 logmsg("instructed to bind port without listening");
1132 /* start accepting connections */
1133 rc = listen(sock, 5);
1136 logmsg("listen(%d, 5) failed with error: (%d) %s",
1137 sock, error, strerror(error));
1139 return CURL_SOCKET_BAD;
1146 int main(int argc, char *argv[])
1148 srvr_sockaddr_union_t me;
1149 curl_socket_t sock = CURL_SOCKET_BAD;
1150 curl_socket_t msgsock = CURL_SOCKET_BAD;
1151 int wrotepidfile = 0;
1152 char *pidname= (char *)".sockfilt.pid";
1157 enum sockmode mode = PASSIVE_LISTEN; /* default */
1158 const char *addr = NULL;
1161 if(!strcmp("--version", argv[arg])) {
1162 printf("sockfilt IPv4%s\n",
1171 else if(!strcmp("--verbose", argv[arg])) {
1175 else if(!strcmp("--pidfile", argv[arg])) {
1178 pidname = argv[arg++];
1180 else if(!strcmp("--logfile", argv[arg])) {
1183 serverlogfile = argv[arg++];
1185 else if(!strcmp("--ipv6", argv[arg])) {
1192 else if(!strcmp("--ipv4", argv[arg])) {
1193 /* for completeness, we support this option as well */
1200 else if(!strcmp("--bindonly", argv[arg])) {
1204 else if(!strcmp("--port", argv[arg])) {
1208 unsigned long ulnum = strtoul(argv[arg], &endptr, 10);
1209 if((endptr != argv[arg] + strlen(argv[arg])) ||
1210 ((ulnum != 0UL) && ((ulnum < 1025UL) || (ulnum > 65535UL)))) {
1211 fprintf(stderr, "sockfilt: invalid --port argument (%s)\n",
1215 port = curlx_ultous(ulnum);
1219 else if(!strcmp("--connect", argv[arg])) {
1220 /* Asked to actively connect to the specified local port instead of
1221 doing a passive server-style listening. */
1225 unsigned long ulnum = strtoul(argv[arg], &endptr, 10);
1226 if((endptr != argv[arg] + strlen(argv[arg])) ||
1227 (ulnum < 1025UL) || (ulnum > 65535UL)) {
1228 fprintf(stderr, "sockfilt: invalid --connect argument (%s)\n",
1232 connectport = curlx_ultous(ulnum);
1236 else if(!strcmp("--addr", argv[arg])) {
1237 /* Set an IP address to use with --connect; otherwise use localhost */
1245 puts("Usage: sockfilt [option]\n"
1248 " --logfile [file]\n"
1249 " --pidfile [file]\n"
1254 " --connect [port]\n"
1255 " --addr [address]");
1262 atexit(win32_cleanup);
1264 setmode(fileno(stdin), O_BINARY);
1265 setmode(fileno(stdout), O_BINARY);
1266 setmode(fileno(stderr), O_BINARY);
1269 install_signal_handlers();
1274 sock = socket(AF_INET, SOCK_STREAM, 0);
1277 sock = socket(AF_INET6, SOCK_STREAM, 0);
1280 if(CURL_SOCKET_BAD == sock) {
1282 logmsg("Error creating socket: (%d) %s",
1283 error, strerror(error));
1284 write_stdout("FAIL\n", 5);
1285 goto sockfilt_cleanup;
1289 /* Active mode, we should connect to the given port number */
1294 memset(&me.sa4, 0, sizeof(me.sa4));
1295 me.sa4.sin_family = AF_INET;
1296 me.sa4.sin_port = htons(connectport);
1297 me.sa4.sin_addr.s_addr = INADDR_ANY;
1300 Curl_inet_pton(AF_INET, addr, &me.sa4.sin_addr);
1302 rc = connect(sock, &me.sa, sizeof(me.sa4));
1306 memset(&me.sa6, 0, sizeof(me.sa6));
1307 me.sa6.sin6_family = AF_INET6;
1308 me.sa6.sin6_port = htons(connectport);
1311 Curl_inet_pton(AF_INET6, addr, &me.sa6.sin6_addr);
1313 rc = connect(sock, &me.sa, sizeof(me.sa6));
1315 #endif /* ENABLE_IPV6 */
1318 logmsg("Error connecting to port %hu: (%d) %s",
1319 connectport, error, strerror(error));
1320 write_stdout("FAIL\n", 5);
1321 goto sockfilt_cleanup;
1323 logmsg("====> Client connect");
1324 msgsock = sock; /* use this as stream */
1327 /* passive daemon style */
1328 sock = sockdaemon(sock, &port);
1329 if(CURL_SOCKET_BAD == sock) {
1330 write_stdout("FAIL\n", 5);
1331 goto sockfilt_cleanup;
1333 msgsock = CURL_SOCKET_BAD; /* no stream socket yet */
1336 logmsg("Running %s version", ipv_inuse);
1339 logmsg("Connected to port %hu", connectport);
1341 logmsg("Bound without listening on port %hu", port);
1343 logmsg("Listening on port %hu", port);
1345 wrotepidfile = write_pidfile(pidname);
1347 write_stdout("FAIL\n", 5);
1348 goto sockfilt_cleanup;
1352 juggle_again = juggle(&msgsock, sock, &mode);
1353 } while(juggle_again);
1357 if((msgsock != sock) && (msgsock != CURL_SOCKET_BAD))
1360 if(sock != CURL_SOCKET_BAD)
1366 restore_signal_handlers();
1368 if(got_exit_signal) {
1369 logmsg("============> sockfilt exits with signal (%d)", exit_signal);
1371 * To properly set the return status of the process we
1372 * must raise the same signal SIGINT or SIGTERM that we
1373 * caught and let the old handler take care of it.
1378 logmsg("============> sockfilt quits");