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.
53 #define DEFINE_PLUG_METHOD_MACROS
59 struct socket_function_table *fn;
60 /* the above variable absolutely *must* be the first in this structure */
68 int frozen; /* this causes readability notifications to be ignored */
69 int frozen_readable; /* this means we missed at least one readability
70 * notification while we were frozen */
77 * We used to typedef struct Socket_tag *Socket.
79 * Since we have made the networking abstraction slightly more
80 * abstract, Socket no longer means a tcp socket (it could mean
81 * an ssl socket). So now we must use Actual_Socket when we know
82 * we are talking about a tcp socket.
84 typedef struct Socket_tag *Actual_Socket;
88 /* address family this belongs to, AF_INET for IPv4, AF_INET6 for IPv6. */
90 unsigned long address; /* Address IPv4 style. */
92 struct addrinfo *ai; /* Address IPv6 style. */
96 static tree234 *sktree;
98 static int cmpfortree(void *av, void *bv)
100 Actual_Socket a = (Actual_Socket) av, b = (Actual_Socket) bv;
101 unsigned long as = (unsigned long) a->s, bs = (unsigned long) b->s;
109 static int cmpforsearch(void *av, void *bv)
111 Actual_Socket b = (Actual_Socket) bv;
112 unsigned long as = (unsigned long) av, bs = (unsigned long) b->s;
122 sktree = newtree234(cmpfortree);
125 char *winsock_error_string(int error)
129 return "Network error: Permission denied";
131 return "Network error: Address already in use";
132 case WSAEADDRNOTAVAIL:
133 return "Network error: Cannot assign requested address";
134 case WSAEAFNOSUPPORT:
136 "Network error: Address family not supported by protocol family";
138 return "Network error: Operation already in progress";
139 case WSAECONNABORTED:
140 return "Network error: Software caused connection abort";
141 case WSAECONNREFUSED:
142 return "Network error: Connection refused";
144 return "Network error: Connection reset by peer";
145 case WSAEDESTADDRREQ:
146 return "Network error: Destination address required";
148 return "Network error: Bad address";
150 return "Network error: Host is down";
151 case WSAEHOSTUNREACH:
152 return "Network error: No route to host";
154 return "Network error: Operation now in progress";
156 return "Network error: Interrupted function call";
158 return "Network error: Invalid argument";
160 return "Network error: Socket is already connected";
162 return "Network error: Too many open files";
164 return "Network error: Message too long";
166 return "Network error: Network is down";
168 return "Network error: Network dropped connection on reset";
170 return "Network error: Network is unreachable";
172 return "Network error: No buffer space available";
174 return "Network error: Bad protocol option";
176 return "Network error: Socket is not connected";
178 return "Network error: Socket operation on non-socket";
180 return "Network error: Operation not supported";
181 case WSAEPFNOSUPPORT:
182 return "Network error: Protocol family not supported";
184 return "Network error: Too many processes";
185 case WSAEPROTONOSUPPORT:
186 return "Network error: Protocol not supported";
188 return "Network error: Protocol wrong type for socket";
190 return "Network error: Cannot send after socket shutdown";
191 case WSAESOCKTNOSUPPORT:
192 return "Network error: Socket type not supported";
194 return "Network error: Connection timed out";
196 return "Network error: Resource temporarily unavailable";
198 return "Network error: Graceful shutdown in progress";
200 return "Unknown network error";
204 SockAddr sk_namelookup(char *host, char **canonicalname)
206 SockAddr ret = smalloc(sizeof(struct SockAddr_tag));
208 struct hostent *h = NULL;
211 /* Clear the structure and default to IPv4. */
212 memset(ret, 0, sizeof(struct SockAddr_tag));
213 ret->family = 0; /* We set this one when we have resolved the host. */
216 if ((a = inet_addr(host)) == (unsigned long) INADDR_NONE) {
219 /* Try to get the getaddrinfo() function from wship6.dll */
220 /* This way one doesn't need to have IPv6 dll's to use PuTTY and
221 * it will fallback to IPv4. */
222 typedef int (CALLBACK * FGETADDRINFO) (const char *nodename,
223 const char *servname,
224 const struct addrinfo *
226 struct addrinfo ** res);
227 FGETADDRINFO fGetAddrInfo = NULL;
229 HINSTANCE dllWSHIP6 = LoadLibrary("wship6.dll");
231 fGetAddrInfo = (FGETADDRINFO) GetProcAddress(dllWSHIP6,
235 * Use fGetAddrInfo when it's available (which usually also
236 * means IPv6 is installed...)
239 /*debug(("Resolving \"%s\" with getaddrinfo() (IPv4+IPv6 capable)...\n", host)); */
240 if (fGetAddrInfo(host, NULL, NULL, &ret->ai) == 0)
241 ret->family = ret->ai->ai_family;
246 * Otherwise use the IPv4-only gethostbyname...
247 * (NOTE: we don't use gethostbyname as a
250 if (ret->family == 0) {
251 /*debug(("Resolving \"%s\" with gethostbyname() (IPv4 only)...\n", host)); */
252 if ( (h = gethostbyname(host)) )
253 ret->family = AF_INET;
256 /*debug(("Done resolving...(family is %d) AF_INET = %d, AF_INET6 = %d\n", ret->family, AF_INET, AF_INET6)); */
258 if (ret->family == 0) {
259 DWORD err = WSAGetLastError();
260 ret->error = (err == WSAENETDOWN ? "Network is down" :
262 WSAHOST_NOT_FOUND ? "Host does not exist" : err
263 == WSATRY_AGAIN ? "Host not found" :
265 fGetAddrInfo ? "getaddrinfo: unknown error" :
267 "gethostbyname: unknown error");
271 FormatMessage(FORMAT_MESSAGE_ALLOCATE_BUFFER |
272 FORMAT_MESSAGE_FROM_SYSTEM |
273 FORMAT_MESSAGE_IGNORE_INSERTS, NULL, err,
274 MAKELANGID(LANG_NEUTRAL, SUBLANG_DEFAULT),
275 (LPTSTR) & lpMsgBuf, 0, NULL);
276 /*debug(("Error %ld: %s (h=%lx)\n", err, lpMsgBuf, h)); */
277 /* Free the buffer. */
285 /* If we got an address info use that... */
287 typedef int (CALLBACK * FGETNAMEINFO)
288 (const struct sockaddr FAR * sa, socklen_t salen,
289 char FAR * host, size_t hostlen, char FAR * serv,
290 size_t servlen, int flags);
291 FGETNAMEINFO fGetNameInfo = NULL;
293 /* Are we in IPv4 fallback mode? */
294 /* We put the IPv4 address into the a variable so we can further-on use the IPv4 code... */
295 if (ret->family == AF_INET)
297 (char *) &((SOCKADDR_IN *) ret->ai->
298 ai_addr)->sin_addr, sizeof(a));
300 /* Now let's find that canonicalname... */
303 (FGETNAMEINFO) GetProcAddress(dllWSHIP6,
306 ((struct sockaddr *) ret->ai->ai_addr,
308 AF_INET ? sizeof(SOCKADDR_IN) :
309 sizeof(SOCKADDR_IN6), realhost,
310 sizeof(realhost), NULL, 0, 0) != 0) {
311 strncpy(realhost, host, sizeof(realhost));
315 /* We used the IPv4-only gethostbyname()... */
319 memcpy(&a, h->h_addr, sizeof(a));
320 /* This way we are always sure the h->h_name is valid :) */
321 strncpy(realhost, h->h_name, sizeof(realhost));
325 FreeLibrary(dllWSHIP6);
329 * This must be a numeric IPv4 address because it caused a
330 * success return from inet_addr.
332 ret->family = AF_INET;
333 strncpy(realhost, host, sizeof(realhost));
335 ret->address = ntohl(a);
336 realhost[lenof(realhost)-1] = '\0';
337 *canonicalname = smalloc(1+strlen(realhost));
338 strcpy(*canonicalname, realhost);
342 void sk_getaddr(SockAddr addr, char *buf, int buflen)
345 if (addr->family == AF_INET) {
348 a.s_addr = htonl(addr->address);
349 strncpy(buf, inet_ntoa(a), buflen);
352 FIXME; /* I don't know how to get a text form of an IPv6 address. */
357 void sk_addr_free(SockAddr addr)
362 static Plug sk_tcp_plug(Socket sock, Plug p)
364 Actual_Socket s = (Actual_Socket) sock;
371 static void sk_tcp_flush(Socket s)
374 * We send data to the socket as soon as we can anyway,
375 * so we don't need to do anything here. :-)
379 static void sk_tcp_close(Socket s);
380 static int sk_tcp_write(Socket s, char *data, int len);
381 static int sk_tcp_write_oob(Socket s, char *data, int len);
382 static char *sk_tcp_socket_error(Socket s);
384 extern char *do_select(SOCKET skt, int startup);
386 Socket sk_register(void *sock, Plug plug)
388 static struct socket_function_table fn_table = {
402 * Create Socket structure.
404 ret = smalloc(sizeof(struct Socket_tag));
408 bufchain_init(&ret->output_data);
409 ret->writable = 1; /* to start with */
410 ret->sending_oob = 0;
412 ret->frozen_readable = 0;
414 ret->s = (SOCKET)sock;
416 if (ret->s == INVALID_SOCKET) {
417 err = WSAGetLastError();
418 ret->error = winsock_error_string(err);
424 /* Set up a select mechanism. This could be an AsyncSelect on a
425 * window, or an EventSelect on an event object. */
426 errstr = do_select(ret->s, 1);
437 Socket sk_new(SockAddr addr, int port, int privport, int oobinline,
440 static struct socket_function_table fn_table = {
460 * Create Socket structure.
462 ret = smalloc(sizeof(struct Socket_tag));
466 bufchain_init(&ret->output_data);
467 ret->connected = 0; /* to start with */
468 ret->writable = 0; /* to start with */
469 ret->sending_oob = 0;
471 ret->frozen_readable = 0;
476 s = socket(addr->family, SOCK_STREAM, 0);
479 if (s == INVALID_SOCKET) {
480 err = WSAGetLastError();
481 ret->error = winsock_error_string(err);
485 ret->oobinline = oobinline;
488 setsockopt(s, SOL_SOCKET, SO_OOBINLINE, (void *) &b, sizeof(b));
492 * Bind to local address.
495 localport = 1023; /* count from 1023 downwards */
497 localport = 0; /* just use port 0 (ie winsock picks) */
499 /* Loop round trying to bind */
504 if (addr->family == AF_INET6) {
505 memset(&a6, 0, sizeof(a6));
506 a6.sin6_family = AF_INET6;
507 /*a6.sin6_addr = in6addr_any; *//* == 0 */
508 a6.sin6_port = htons(localport);
512 a.sin_family = AF_INET;
513 a.sin_addr.s_addr = htonl(INADDR_ANY);
514 a.sin_port = htons(localport);
517 retcode = bind(s, (addr->family == AF_INET6 ?
518 (struct sockaddr *) &a6 :
519 (struct sockaddr *) &a),
521 AF_INET6 ? sizeof(a6) : sizeof(a)));
523 retcode = bind(s, (struct sockaddr *) &a, sizeof(a));
525 if (retcode != SOCKET_ERROR) {
529 err = WSAGetLastError();
530 if (err != WSAEADDRINUSE) /* failed, for a bad reason */
535 break; /* we're only looping once */
538 break; /* we might have got to the end */
542 ret->error = winsock_error_string(err);
547 * Connect to remote address.
550 if (addr->family == AF_INET6) {
551 memset(&a, 0, sizeof(a));
552 a6.sin6_family = AF_INET6;
553 a6.sin6_port = htons((short) port);
555 ((struct sockaddr_in6 *) addr->ai->ai_addr)->sin6_addr;
559 a.sin_family = AF_INET;
560 a.sin_addr.s_addr = htonl(addr->address);
561 a.sin_port = htons((short) port);
564 /* Set up a select mechanism. This could be an AsyncSelect on a
565 * window, or an EventSelect on an event object. */
566 errstr = do_select(s, 1);
574 connect(s, ((addr->family == AF_INET6) ?
575 (struct sockaddr *) &a6 : (struct sockaddr *) &a),
576 (addr->family == AF_INET6) ? sizeof(a6) : sizeof(a))
578 connect(s, (struct sockaddr *) &a, sizeof(a))
581 err = WSAGetLastError();
583 * We expect a potential EWOULDBLOCK here, because the
584 * chances are the front end has done a select for
585 * FD_CONNECT, so that connect() will complete
588 if ( err != WSAEWOULDBLOCK ) {
589 ret->error = winsock_error_string(err);
594 * If we _don't_ get EWOULDBLOCK, the connect has completed
595 * and we should set the socket as writable.
605 Socket sk_newlistener(int port, Plug plug, int local_host_only)
607 static struct socket_function_table fn_table = {
628 * Create Socket structure.
630 ret = smalloc(sizeof(struct Socket_tag));
634 bufchain_init(&ret->output_data);
635 ret->writable = 0; /* to start with */
636 ret->sending_oob = 0;
638 ret->frozen_readable = 0;
643 s = socket(AF_INET, SOCK_STREAM, 0);
646 if (s == INVALID_SOCKET) {
647 err = WSAGetLastError();
648 ret->error = winsock_error_string(err);
655 setsockopt(s, SOL_SOCKET, SO_REUSEADDR, (const char *)&on, sizeof(on));
659 if (addr->family == AF_INET6) {
660 memset(&a6, 0, sizeof(a6));
661 a6.sin6_family = AF_INET6;
663 a6.sin6_addr = in6addr_loopback;
665 a6.sin6_addr = in6addr_any;
666 a6.sin6_port = htons(port);
670 a.sin_family = AF_INET;
672 a.sin_addr.s_addr = htonl(INADDR_LOOPBACK);
674 a.sin_addr.s_addr = htonl(INADDR_ANY);
675 a.sin_port = htons((short)port);
678 retcode = bind(s, (addr->family == AF_INET6 ?
679 (struct sockaddr *) &a6 :
680 (struct sockaddr *) &a),
682 AF_INET6 ? sizeof(a6) : sizeof(a)));
684 retcode = bind(s, (struct sockaddr *) &a, sizeof(a));
686 if (retcode != SOCKET_ERROR) {
689 err = WSAGetLastError();
693 ret->error = winsock_error_string(err);
698 if (listen(s, SOMAXCONN) == SOCKET_ERROR) {
700 ret->error = winsock_error_string(err);
704 /* Set up a select mechanism. This could be an AsyncSelect on a
705 * window, or an EventSelect on an event object. */
706 errstr = do_select(s, 1);
717 static void sk_tcp_close(Socket sock)
719 extern char *do_select(SOCKET skt, int startup);
720 Actual_Socket s = (Actual_Socket) sock;
729 * The function which tries to send on a socket once it's deemed
732 void try_send(Actual_Socket s)
734 while (s->sending_oob || bufchain_size(&s->output_data) > 0) {
740 if (s->sending_oob) {
741 urgentflag = MSG_OOB;
742 len = s->sending_oob;
746 bufchain_prefix(&s->output_data, &data, &len);
748 nsent = send(s->s, data, len, urgentflag);
749 noise_ultralight(nsent);
751 err = (nsent < 0 ? WSAGetLastError() : 0);
752 if ((err < WSABASEERR && nsent < 0) || err == WSAEWOULDBLOCK) {
754 * Perfectly normal: we've sent all we can for the moment.
756 * (Some WinSock send() implementations can return
757 * <0 but leave no sensible error indication -
758 * WSAGetLastError() is called but returns zero or
759 * a small number - so we check that case and treat
760 * it just like WSAEWOULDBLOCK.)
764 } else if (nsent == 0 ||
765 err == WSAECONNABORTED || err == WSAECONNRESET) {
769 * I'm assuming here that if a TCP connection is
770 * reset or aborted once established, we will be
771 * notified by a select event rather than a
772 * CONNABORTED or CONNRESET from send(). In other
773 * words, I'm assuming CONNABORTED and CONNRESET
774 * don't come back from a _nonblocking_ send(),
775 * because the local side doesn't know they've
776 * happened until it waits for a response to its
777 * TCP segment - so the error will arrive
780 * If I'm wrong, this will be a really nasty case,
781 * because we can't necessarily call plug_closing()
782 * without having to make half the SSH code
783 * reentrant; so instead we'll have to schedule a
784 * call to plug_closing() for some suitable future
787 fatalbox("SERIOUS NETWORK INTERNAL ERROR: %s\n"
788 "Please report this immediately to "
789 "<putty@projects.tartarus.org>.",
790 winsock_error_string(err));
792 fatalbox(winsock_error_string(err));
795 if (s->sending_oob) {
797 memmove(s->oobdata, s->oobdata+nsent, len-nsent);
798 s->sending_oob = len - nsent;
803 bufchain_consume(&s->output_data, nsent);
809 static int sk_tcp_write(Socket sock, char *buf, int len)
811 Actual_Socket s = (Actual_Socket) sock;
814 * Add the data to the buffer list on the socket.
816 bufchain_add(&s->output_data, buf, len);
819 * Now try sending from the start of the buffer list.
824 return bufchain_size(&s->output_data);
827 static int sk_tcp_write_oob(Socket sock, char *buf, int len)
829 Actual_Socket s = (Actual_Socket) sock;
832 * Replace the buffer list on the socket with the data.
834 bufchain_clear(&s->output_data);
835 assert(len <= sizeof(s->oobdata));
836 memcpy(s->oobdata, buf, len);
837 s->sending_oob = len;
840 * Now try sending from the start of the buffer list.
845 return s->sending_oob;
848 int select_result(WPARAM wParam, LPARAM lParam)
852 char buf[20480]; /* nice big buffer for plenty of speed */
856 /* wParam is the socket itself */
857 s = find234(sktree, (void *) wParam, cmpforsearch);
859 return 1; /* boggle */
861 if ((err = WSAGETSELECTERROR(lParam)) != 0) {
863 * An error has occurred on this socket. Pass it to the
866 return plug_closing(s->plug, winsock_error_string(err), err, 0);
869 noise_ultralight(lParam);
871 switch (WSAGETSELECTEVENT(lParam)) {
873 s->connected = s->writable = 1;
876 /* In the case the socket is still frozen, we don't even bother */
878 s->frozen_readable = 1;
883 * We have received data on the socket. For an oobinline
884 * socket, this might be data _before_ an urgent pointer,
885 * in which case we send it to the back end with type==1
886 * (data prior to urgent).
890 ioctlsocket(s->s, SIOCATMARK, &atmark);
892 * Avoid checking the return value from ioctlsocket(),
893 * on the grounds that some WinSock wrappers don't
894 * support it. If it does nothing, we get atmark==1,
895 * which is equivalent to `no OOB pending', so the
896 * effect will be to non-OOB-ify any OOB data.
901 ret = recv(s->s, buf, sizeof(buf), 0);
902 noise_ultralight(ret);
904 err = WSAGetLastError();
905 if (err == WSAEWOULDBLOCK) {
910 return plug_closing(s->plug, winsock_error_string(err), err,
912 } else if (0 == ret) {
913 return plug_closing(s->plug, NULL, 0, 0);
915 return plug_receive(s->plug, atmark ? 0 : 1, buf, ret);
920 * This will only happen on a non-oobinline socket. It
921 * indicates that we can immediately perform an OOB read
922 * and get back OOB data, which we will send to the back
923 * end with type==2 (urgent data).
925 ret = recv(s->s, buf, sizeof(buf), MSG_OOB);
926 noise_ultralight(ret);
928 fatalbox(ret == 0 ? "Internal networking trouble" :
929 winsock_error_string(WSAGetLastError()));
931 return plug_receive(s->plug, 2, buf, ret);
936 int bufsize_before, bufsize_after;
938 bufsize_before = s->sending_oob + bufchain_size(&s->output_data);
940 bufsize_after = s->sending_oob + bufchain_size(&s->output_data);
941 if (bufsize_after < bufsize_before)
942 plug_sent(s->plug, bufsize_after);
946 /* Signal a close on the socket. First read any outstanding data. */
949 ret = recv(s->s, buf, sizeof(buf), 0);
951 err = WSAGetLastError();
952 if (err == WSAEWOULDBLOCK)
954 return plug_closing(s->plug, winsock_error_string(err),
958 open &= plug_receive(s->plug, 0, buf, ret);
960 open &= plug_closing(s->plug, NULL, 0, 0);
967 int addrlen = sizeof(struct sockaddr);
968 SOCKET t; /* socket of connection */
970 memset(&isa, 0, sizeof(struct sockaddr));
972 t = accept(s->s,&isa,&addrlen);
973 if (t == INVALID_SOCKET)
975 err = WSAGetLastError();
976 if (err == WSATRY_AGAIN)
980 if (plug_accepting(s->plug, (void*)t)) {
981 closesocket(t); /* denied or error */
990 * Each socket abstraction contains a `void *' private field in
991 * which the client can keep state.
993 void sk_set_private_ptr(Socket sock, void *ptr)
995 Actual_Socket s = (Actual_Socket) sock;
996 s->private_ptr = ptr;
999 void *sk_get_private_ptr(Socket sock)
1001 Actual_Socket s = (Actual_Socket) sock;
1002 return s->private_ptr;
1006 * Special error values are returned from sk_namelookup and sk_new
1007 * if there's a problem. These functions extract an error message,
1008 * or return NULL if there's no problem.
1010 char *sk_addr_error(SockAddr addr)
1014 static char *sk_tcp_socket_error(Socket sock)
1016 Actual_Socket s = (Actual_Socket) sock;
1020 void sk_set_frozen(Socket sock, int is_frozen)
1022 Actual_Socket s = (Actual_Socket) sock;
1023 if (s->frozen == is_frozen)
1025 s->frozen = is_frozen;
1026 if (!is_frozen && s->frozen_readable) {
1028 recv(s->s, &c, 1, MSG_PEEK);
1030 s->frozen_readable = 0;
1034 * For Plink: enumerate all sockets currently active.
1036 SOCKET first_socket(int *state)
1040 s = index234(sktree, (*state)++);
1041 return s ? s->s : INVALID_SOCKET;
1044 SOCKET next_socket(int *state)
1046 Actual_Socket s = index234(sktree, (*state)++);
1047 return s ? s->s : INVALID_SOCKET;