2 * Windows networking abstraction.
4 * Due to this clean abstraction it was possible
5 * to easily implement IPv6 support :)
7 * IPv6 patch 1 (27 October 2000) Jeroen Massar <jeroen@unfix.org>
8 * - Preliminary hacked IPv6 support.
9 * - Connecting to IPv6 address (eg fec0:4242:4242:100:2d0:b7ff:fe8f:5d42) works.
10 * - Connecting to IPv6 hostname (eg heaven.ipv6.unfix.org) works.
11 * - Compiles as either IPv4 or IPv6.
13 * IPv6 patch 2 (29 October 2000) Jeroen Massar <jeroen@unfix.org>
14 * - When compiled as IPv6 it also allows connecting to IPv4 hosts.
15 * - Added some more documentation.
17 * IPv6 patch 3 (18 November 2000) Jeroen Massar <jeroen@unfix.org>
18 * - It now supports dynamically loading the IPv6 resolver dll's.
19 * This way we should be able to distribute one (1) binary
20 * which supports both IPv4 and IPv6.
21 * - getaddrinfo() and getnameinfo() are loaded dynamicaly if possible.
22 * - in6addr_any is defined in this file so we don't need to link to wship6.lib
23 * - The patch is now more unified so that we can still
24 * remove all IPv6 support by undef'ing IPV6.
25 * But where it fallsback to IPv4 it uses the IPv4 code which is already in place...
26 * - Canonical name resolving works.
28 * IPv6 patch 4 (07 January 2001) Jeroen Massar <jeroen@unfix.org>
29 * - patch against CVS of today, will be submitted to the bugs list
30 * as a 'cvs diff -u' on Simon's request...
35 * Define IPV6 to have IPv6 on-the-fly-loading support.
36 * This means that one doesn't have to have an IPv6 stack to use it.
37 * But if an IPv6 stack is found it is used with a fallback to IPv4.
52 #define DEFINE_PLUG_METHOD_MACROS
57 #define BUFFER_GRANULE 512
60 struct socket_function_table *fn;
61 /* the above variable absolutely *must* be the first in this structure */
66 struct buffer *head, *tail;
73 * We used to typedef struct Socket_tag *Socket.
75 * Since we have made the networking abstraction slightly more
76 * abstract, Socket no longer means a tcp socket (it could mean
77 * an ssl socket). So now we must use Actual_Socket when we know
78 * we are talking about a tcp socket.
80 typedef struct Socket_tag *Actual_Socket;
84 /* address family this belongs to, AF_INET for IPv4, AF_INET6 for IPv6. */
86 unsigned long address; /* Address IPv4 style. */
88 struct addrinfo *ai; /* Address IPv6 style. */
91 * We need to have this lengthy enough to hold *any* hostname
92 * (including IPv6 reverse...)
100 char buf[BUFFER_GRANULE];
103 static tree234 *sktree;
105 static int cmpfortree(void *av, void *bv)
107 Actual_Socket a = (Actual_Socket) av, b = (Actual_Socket) bv;
108 unsigned long as = (unsigned long) a->s, bs = (unsigned long) b->s;
116 static int cmpforsearch(void *av, void *bv)
118 Actual_Socket b = (Actual_Socket) bv;
119 unsigned long as = (unsigned long) av, bs = (unsigned long) b->s;
129 sktree = newtree234(cmpfortree);
132 char *winsock_error_string(int error)
136 return "Network error: Permission denied";
138 return "Network error: Address already in use";
139 case WSAEADDRNOTAVAIL:
140 return "Network error: Cannot assign requested address";
141 case WSAEAFNOSUPPORT:
143 "Network error: Address family not supported by protocol family";
145 return "Network error: Operation already in progress";
146 case WSAECONNABORTED:
147 return "Network error: Software caused connection abort";
148 case WSAECONNREFUSED:
149 return "Network error: Connection refused";
151 return "Network error: Connection reset by peer";
152 case WSAEDESTADDRREQ:
153 return "Network error: Destination address required";
155 return "Network error: Bad address";
157 return "Network error: Host is down";
158 case WSAEHOSTUNREACH:
159 return "Network error: No route to host";
161 return "Network error: Operation now in progress";
163 return "Network error: Interrupted function call";
165 return "Network error: Invalid argument";
167 return "Network error: Socket is already connected";
169 return "Network error: Too many open files";
171 return "Network error: Message too long";
173 return "Network error: Network is down";
175 return "Network error: Network dropped connection on reset";
177 return "Network error: Network is unreachable";
179 return "Network error: No buffer space available";
181 return "Network error: Bad protocol option";
183 return "Network error: Socket is not connected";
185 return "Network error: Socket operation on non-socket";
187 return "Network error: Operation not supported";
188 case WSAEPFNOSUPPORT:
189 return "Network error: Protocol family not supported";
191 return "Network error: Too many processes";
192 case WSAEPROTONOSUPPORT:
193 return "Network error: Protocol not supported";
195 return "Network error: Protocol wrong type for socket";
197 return "Network error: Cannot send after socket shutdown";
198 case WSAESOCKTNOSUPPORT:
199 return "Network error: Socket type not supported";
201 return "Network error: Connection timed out";
203 return "Network error: Resource temporarily unavailable";
205 return "Network error: Graceful shutdown in progress";
207 return "Unknown network error";
211 SockAddr sk_namelookup(char *host, char **canonicalname)
213 SockAddr ret = smalloc(sizeof(struct SockAddr_tag));
215 struct hostent *h = NULL;
217 /* Clear the structure and default to IPv4. */
218 memset(ret, 0, sizeof(struct SockAddr_tag));
219 ret->family = 0; /* We set this one when we have resolved the host. */
220 *canonicalname = ret->realhost; /* This makes sure we always have a hostname to return. */
222 if ((a = inet_addr(host)) == (unsigned long) INADDR_NONE) {
225 /* Try to get the getaddrinfo() function from wship6.dll */
226 /* This way one doesn't need to have IPv6 dll's to use PuTTY and
227 * it will fallback to IPv4. */
228 typedef int (CALLBACK * FGETADDRINFO) (const char *nodename,
229 const char *servname,
230 const struct addrinfo *
232 struct addrinfo ** res);
233 FGETADDRINFO fGetAddrInfo = NULL;
235 HINSTANCE dllWSHIP6 = LoadLibrary("wship6.dll");
237 fGetAddrInfo = (FGETADDRINFO) GetProcAddress(dllWSHIP6,
241 * Use fGetAddrInfo when it's available (which usually also
242 * means IPv6 is installed...)
245 /*debug(("Resolving \"%s\" with getaddrinfo() (IPv4+IPv6 capable)...\n", host)); */
246 if (fGetAddrInfo(host, NULL, NULL, &ret->ai) == 0)
247 ret->family = ret->ai->ai_family;
252 * Otherwise use the IPv4-only gethostbyname...
253 * (NOTE: we don't use gethostbyname as a
256 if (ret->family == 0) {
257 /*debug(("Resolving \"%s\" with gethostbyname() (IPv4 only)...\n", host)); */
258 if (h = gethostbyname(host))
259 ret->family = AF_INET;
262 /*debug(("Done resolving...(family is %d) AF_INET = %d, AF_INET6 = %d\n", ret->family, AF_INET, AF_INET6)); */
264 if (ret->family == 0) {
265 DWORD err = WSAGetLastError();
266 ret->error = (err == WSAENETDOWN ? "Network is down" :
268 WSAHOST_NOT_FOUND ? "Host does not exist" : err
269 == WSATRY_AGAIN ? "Host not found" :
271 fGetAddrInfo ? "getaddrinfo: unknown error" :
273 "gethostbyname: unknown error");
277 FormatMessage(FORMAT_MESSAGE_ALLOCATE_BUFFER |
278 FORMAT_MESSAGE_FROM_SYSTEM |
279 FORMAT_MESSAGE_IGNORE_INSERTS, NULL, err,
280 MAKELANGID(LANG_NEUTRAL, SUBLANG_DEFAULT),
281 (LPTSTR) & lpMsgBuf, 0, NULL);
282 /*debug(("Error %ld: %s (h=%lx)\n", err, lpMsgBuf, h)); */
283 /* Free the buffer. */
291 /* If we got an address info use that... */
293 typedef int (CALLBACK * FGETNAMEINFO)
294 (const struct sockaddr FAR * sa, socklen_t salen,
295 char FAR * host, size_t hostlen, char FAR * serv,
296 size_t servlen, int flags);
297 FGETNAMEINFO fGetNameInfo = NULL;
299 /* Are we in IPv4 fallback mode? */
300 /* We put the IPv4 address into the a variable so we can further-on use the IPv4 code... */
301 if (ret->family == AF_INET)
303 (char *) &((SOCKADDR_IN *) ret->ai->
304 ai_addr)->sin_addr, sizeof(a));
306 /* Now let's find that canonicalname... */
309 (FGETNAMEINFO) GetProcAddress(dllWSHIP6,
312 ((struct sockaddr *) ret->ai->ai_addr,
314 AF_INET ? sizeof(SOCKADDR_IN) :
315 sizeof(SOCKADDR_IN6), ret->realhost,
316 sizeof(ret->realhost), NULL, 0, 0) != 0) {
317 strncpy(ret->realhost, host,
318 sizeof(ret->realhost));
322 /* We used the IPv4-only gethostbyname()... */
326 memcpy(&a, h->h_addr, sizeof(a));
327 /* This way we are always sure the h->h_name is valid :) */
328 strncpy(ret->realhost, h->h_name, sizeof(ret->realhost));
332 FreeLibrary(dllWSHIP6);
336 * This must be a numeric IPv4 address because it caused a
337 * success return from inet_addr.
339 ret->family = AF_INET;
340 *canonicalname = host;
342 ret->address = ntohl(a);
346 void sk_addr_free(SockAddr addr)
351 static Plug sk_tcp_plug(Socket sock, Plug p)
353 Actual_Socket s = (Actual_Socket) sock;
360 static void sk_tcp_flush(Socket s)
363 * We send data to the socket as soon as we can anyway,
364 * so we don't need to do anything here. :-)
368 void sk_tcp_close(Socket s);
369 void sk_tcp_write(Socket s, char *data, int len);
370 void sk_tcp_write_oob(Socket s, char *data, int len);
371 char *sk_tcp_socket_error(Socket s);
373 Socket sk_new(SockAddr addr, int port, int privport, int oobinline,
376 static struct socket_function_table fn_table = {
393 extern char *do_select(SOCKET skt, int startup);
397 * Create Socket structure.
399 ret = smalloc(sizeof(struct Socket_tag));
403 ret->head = ret->tail = NULL;
404 ret->writable = 1; /* to start with */
405 ret->sending_oob = 0;
410 s = socket(addr->family, SOCK_STREAM, 0);
413 if (s == INVALID_SOCKET) {
414 err = WSAGetLastError();
415 ret->error = winsock_error_string(err);
419 ret->oobinline = oobinline;
422 setsockopt(s, SOL_SOCKET, SO_OOBINLINE, (void *) &b, sizeof(b));
426 * Bind to local address.
429 localport = 1023; /* count from 1023 downwards */
431 localport = 0; /* just use port 0 (ie winsock picks) */
433 /* Loop round trying to bind */
438 if (addr->family == AF_INET6) {
439 memset(&a6, 0, sizeof(a6));
440 a6.sin6_family = AF_INET6;
441 /*a6.sin6_addr = in6addr_any; *//* == 0 */
442 a6.sin6_port = htons(localport);
446 a.sin_family = AF_INET;
447 a.sin_addr.s_addr = htonl(INADDR_ANY);
448 a.sin_port = htons(localport);
451 retcode = bind(s, (addr->family == AF_INET6 ?
452 (struct sockaddr *) &a6 :
453 (struct sockaddr *) &a),
455 AF_INET6 ? sizeof(a6) : sizeof(a)));
457 retcode = bind(s, (struct sockaddr *) &a, sizeof(a));
459 if (retcode != SOCKET_ERROR) {
463 err = WSAGetLastError();
464 if (err != WSAEADDRINUSE) /* failed, for a bad reason */
469 break; /* we're only looping once */
472 break; /* we might have got to the end */
476 ret->error = winsock_error_string(err);
481 * Connect to remote address.
484 if (addr->family == AF_INET6) {
485 memset(&a, 0, sizeof(a));
486 a6.sin6_family = AF_INET6;
487 a6.sin6_port = htons((short) port);
489 ((struct sockaddr_in6 *) addr->ai->ai_addr)->sin6_addr;
493 a.sin_family = AF_INET;
494 a.sin_addr.s_addr = htonl(addr->address);
495 a.sin_port = htons((short) port);
499 connect(s, ((addr->family == AF_INET6) ?
500 (struct sockaddr *) &a6 : (struct sockaddr *) &a),
501 (addr->family == AF_INET6) ? sizeof(a6) : sizeof(a))
503 connect(s, (struct sockaddr *) &a, sizeof(a))
506 err = WSAGetLastError();
507 ret->error = winsock_error_string(err);
511 /* Set up a select mechanism. This could be an AsyncSelect on a
512 * window, or an EventSelect on an event object. */
513 errstr = do_select(s, 1);
524 static void sk_tcp_close(Socket sock)
526 extern char *do_select(SOCKET skt, int startup);
527 Actual_Socket s = (Actual_Socket) sock;
536 * The function which tries to send on a socket once it's deemed
539 void try_send(Actual_Socket s)
546 if (s->sending_oob) {
547 urgentflag = MSG_OOB;
548 len = s->sending_oob;
551 len = s->head->buflen - s->head->bufpos;
555 send(s->s, s->head->buf + s->head->bufpos, len, urgentflag);
556 noise_ultralight(nsent);
558 err = (nsent < 0 ? WSAGetLastError() : 0);
559 if ((err == 0 && nsent < 0) || err == WSAEWOULDBLOCK) {
561 * Perfectly normal: we've sent all we can for the moment.
563 * (Apparently some WinSocks can return <0 but
564 * leave no error indication - WSAGetLastError() is
565 * called but returns zero - so we check that case
566 * and treat it just like WSAEWOULDBLOCK.)
570 } else if (nsent == 0 ||
571 err == WSAECONNABORTED || err == WSAECONNRESET) {
573 * FIXME. This will have to be done better when we
574 * start managing multiple sockets (e.g. SSH port
575 * forwarding), because if we get CONNRESET while
576 * trying to write a particular forwarded socket
577 * then it isn't necessarily the end of the world.
578 * Ideally I'd like to pass the error code back to
579 * somewhere the next select_result() will see it,
580 * but that might be hard. Perhaps I should pass it
581 * back to be queued in the Windows front end bit.
583 fatalbox(winsock_error_string(err));
585 fatalbox(winsock_error_string(err));
588 s->head->bufpos += nsent;
590 s->sending_oob -= nsent;
591 if (s->head->bufpos >= s->head->buflen) {
592 struct buffer *tmp = s->head;
602 static void sk_tcp_write(Socket sock, char *buf, int len)
604 Actual_Socket s = (Actual_Socket) sock;
607 * Add the data to the buffer list on the socket.
609 if (s->tail && s->tail->buflen < BUFFER_GRANULE) {
610 int copylen = min(len, BUFFER_GRANULE - s->tail->buflen);
611 memcpy(s->tail->buf + s->tail->buflen, buf, copylen);
614 s->tail->buflen += copylen;
617 int grainlen = min(len, BUFFER_GRANULE);
618 struct buffer *newbuf;
619 newbuf = smalloc(sizeof(struct buffer));
621 newbuf->buflen = grainlen;
622 memcpy(newbuf->buf, buf, grainlen);
626 s->tail->next = newbuf;
628 s->head = s->tail = newbuf;
634 * Now try sending from the start of the buffer list.
640 static void sk_tcp_write_oob(Socket sock, char *buf, int len)
642 Actual_Socket s = (Actual_Socket) sock;
645 * Replace the buffer list on the socket with the data.
648 s->head = smalloc(sizeof(struct buffer));
650 struct buffer *walk = s->head->next;
652 struct buffer *tmp = walk;
657 s->head->next = NULL;
659 s->head->buflen = len;
660 memcpy(s->head->buf, buf, len);
663 * Set the Urgent marker.
665 s->sending_oob = len;
668 * Now try sending from the start of the buffer list.
674 int select_result(WPARAM wParam, LPARAM lParam)
678 char buf[20480]; /* nice big buffer for plenty of speed */
682 /* wParam is the socket itself */
683 s = find234(sktree, (void *) wParam, cmpforsearch);
685 return 1; /* boggle */
687 if ((err = WSAGETSELECTERROR(lParam)) != 0) {
689 * An error has occurred on this socket. Pass it to the
692 return plug_closing(s->plug, winsock_error_string(err), err, 0);
695 noise_ultralight(lParam);
697 switch (WSAGETSELECTEVENT(lParam)) {
700 * We have received data on the socket. For an oobinline
701 * socket, this might be data _before_ an urgent pointer,
702 * in which case we send it to the back end with type==1
703 * (data prior to urgent).
707 ioctlsocket(s->s, SIOCATMARK, &atmark);
709 * Avoid checking the return value from ioctlsocket(),
710 * on the grounds that some WinSock wrappers don't
711 * support it. If it does nothing, we get atmark==1,
712 * which is equivalent to `no OOB pending', so the
713 * effect will be to non-OOB-ify any OOB data.
718 ret = recv(s->s, buf, sizeof(buf), 0);
719 noise_ultralight(ret);
721 err = WSAGetLastError();
722 if (err == WSAEWOULDBLOCK) {
727 return plug_closing(s->plug, winsock_error_string(err), err,
729 } else if (0 == ret) {
730 return plug_closing(s->plug, NULL, 0, 0);
732 return plug_receive(s->plug, atmark ? 0 : 1, buf, ret);
737 * This will only happen on a non-oobinline socket. It
738 * indicates that we can immediately perform an OOB read
739 * and get back OOB data, which we will send to the back
740 * end with type==2 (urgent data).
742 ret = recv(s->s, buf, sizeof(buf), MSG_OOB);
743 noise_ultralight(ret);
745 fatalbox(ret == 0 ? "Internal networking trouble" :
746 winsock_error_string(WSAGetLastError()));
748 return plug_receive(s->plug, 2, buf, ret);
756 /* Signal a close on the socket. First read any outstanding data. */
759 ret = recv(s->s, buf, sizeof(buf), 0);
761 err = WSAGetLastError();
762 if (err == WSAEWOULDBLOCK)
764 return plug_closing(s->plug, winsock_error_string(err),
768 open &= plug_receive(s->plug, 0, buf, ret);
770 open &= plug_closing(s->plug, NULL, 0, 0);
780 * Each socket abstraction contains a `void *' private field in
781 * which the client can keep state.
783 void sk_set_private_ptr(Socket sock, void *ptr)
785 Actual_Socket s = (Actual_Socket) sock;
786 s->private_ptr = ptr;
789 void *sk_get_private_ptr(Socket sock)
791 Actual_Socket s = (Actual_Socket) sock;
792 return s->private_ptr;
796 * Special error values are returned from sk_namelookup and sk_new
797 * if there's a problem. These functions extract an error message,
798 * or return NULL if there's no problem.
800 char *sk_addr_error(SockAddr addr)
804 static char *sk_tcp_socket_error(Socket sock)
806 Actual_Socket s = (Actual_Socket) sock;
811 * For Plink: enumerate all sockets currently active.
813 SOCKET first_socket(int *state)
817 s = index234(sktree, (*state)++);
818 return s ? s->s : INVALID_SOCKET;
821 SOCKET next_socket(int *state)
823 Actual_Socket s = index234(sktree, (*state)++);
824 return s ? s->s : INVALID_SOCKET;