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
58 #define ipv4_is_loopback(addr) \
59 ((ntohl(addr.s_addr) & 0xFF000000L) == 0x7F000000L)
62 struct socket_function_table *fn;
63 /* the above variable absolutely *must* be the first in this structure */
71 int frozen; /* this causes readability notifications to be ignored */
72 int frozen_readable; /* this means we missed at least one readability
73 * notification while we were frozen */
74 int localhost_only; /* for listening sockets */
78 int pending_error; /* in case send() returns error */
82 * We used to typedef struct Socket_tag *Socket.
84 * Since we have made the networking abstraction slightly more
85 * abstract, Socket no longer means a tcp socket (it could mean
86 * an ssl socket). So now we must use Actual_Socket when we know
87 * we are talking about a tcp socket.
89 typedef struct Socket_tag *Actual_Socket;
94 * Which address family this address belongs to. AF_INET for
95 * IPv4; AF_INET6 for IPv6; AF_UNSPEC indicates that name
96 * resolution has not been done and a simple host name is held
97 * in this SockAddr structure.
100 unsigned long address; /* Address IPv4 style. */
102 struct addrinfo *ai; /* Address IPv6 style. */
104 char hostname[512]; /* Store an unresolved host name. */
107 static tree234 *sktree;
109 static int cmpfortree(void *av, void *bv)
111 Actual_Socket a = (Actual_Socket) av, b = (Actual_Socket) bv;
112 unsigned long as = (unsigned long) a->s, bs = (unsigned long) b->s;
120 static int cmpforsearch(void *av, void *bv)
122 Actual_Socket b = (Actual_Socket) bv;
123 unsigned long as = (unsigned long) av, bs = (unsigned long) b->s;
133 sktree = newtree234(cmpfortree);
136 void sk_cleanup(void)
142 for (i = 0; (s = index234(sktree, i)) != NULL; i++) {
148 char *winsock_error_string(int error)
152 return "Network error: Permission denied";
154 return "Network error: Address already in use";
155 case WSAEADDRNOTAVAIL:
156 return "Network error: Cannot assign requested address";
157 case WSAEAFNOSUPPORT:
159 "Network error: Address family not supported by protocol family";
161 return "Network error: Operation already in progress";
162 case WSAECONNABORTED:
163 return "Network error: Software caused connection abort";
164 case WSAECONNREFUSED:
165 return "Network error: Connection refused";
167 return "Network error: Connection reset by peer";
168 case WSAEDESTADDRREQ:
169 return "Network error: Destination address required";
171 return "Network error: Bad address";
173 return "Network error: Host is down";
174 case WSAEHOSTUNREACH:
175 return "Network error: No route to host";
177 return "Network error: Operation now in progress";
179 return "Network error: Interrupted function call";
181 return "Network error: Invalid argument";
183 return "Network error: Socket is already connected";
185 return "Network error: Too many open files";
187 return "Network error: Message too long";
189 return "Network error: Network is down";
191 return "Network error: Network dropped connection on reset";
193 return "Network error: Network is unreachable";
195 return "Network error: No buffer space available";
197 return "Network error: Bad protocol option";
199 return "Network error: Socket is not connected";
201 return "Network error: Socket operation on non-socket";
203 return "Network error: Operation not supported";
204 case WSAEPFNOSUPPORT:
205 return "Network error: Protocol family not supported";
207 return "Network error: Too many processes";
208 case WSAEPROTONOSUPPORT:
209 return "Network error: Protocol not supported";
211 return "Network error: Protocol wrong type for socket";
213 return "Network error: Cannot send after socket shutdown";
214 case WSAESOCKTNOSUPPORT:
215 return "Network error: Socket type not supported";
217 return "Network error: Connection timed out";
219 return "Network error: Resource temporarily unavailable";
221 return "Network error: Graceful shutdown in progress";
223 return "Unknown network error";
227 SockAddr sk_namelookup(char *host, char **canonicalname)
229 SockAddr ret = smalloc(sizeof(struct SockAddr_tag));
231 struct hostent *h = NULL;
234 /* Clear the structure and default to IPv4. */
235 memset(ret, 0, sizeof(struct SockAddr_tag));
236 ret->family = 0; /* We set this one when we have resolved the host. */
239 if ((a = inet_addr(host)) == (unsigned long) INADDR_NONE) {
242 /* Try to get the getaddrinfo() function from wship6.dll */
243 /* This way one doesn't need to have IPv6 dll's to use PuTTY and
244 * it will fallback to IPv4. */
245 typedef int (CALLBACK * FGETADDRINFO) (const char *nodename,
246 const char *servname,
247 const struct addrinfo *
249 struct addrinfo ** res);
250 FGETADDRINFO fGetAddrInfo = NULL;
252 HINSTANCE dllWSHIP6 = LoadLibrary("wship6.dll");
254 fGetAddrInfo = (FGETADDRINFO) GetProcAddress(dllWSHIP6,
258 * Use fGetAddrInfo when it's available (which usually also
259 * means IPv6 is installed...)
262 /*debug(("Resolving \"%s\" with getaddrinfo() (IPv4+IPv6 capable)...\n", host)); */
263 if (fGetAddrInfo(host, NULL, NULL, &ret->ai) == 0)
264 ret->family = ret->ai->ai_family;
269 * Otherwise use the IPv4-only gethostbyname...
270 * (NOTE: we don't use gethostbyname as a
273 if (ret->family == 0) {
274 /*debug(("Resolving \"%s\" with gethostbyname() (IPv4 only)...\n", host)); */
275 if ( (h = gethostbyname(host)) )
276 ret->family = AF_INET;
279 /*debug(("Done resolving...(family is %d) AF_INET = %d, AF_INET6 = %d\n", ret->family, AF_INET, AF_INET6)); */
281 if (ret->family == 0) {
282 DWORD err = WSAGetLastError();
283 ret->error = (err == WSAENETDOWN ? "Network is down" :
285 WSAHOST_NOT_FOUND ? "Host does not exist" : err
286 == WSATRY_AGAIN ? "Host not found" :
288 fGetAddrInfo ? "getaddrinfo: unknown error" :
290 "gethostbyname: unknown error");
294 FormatMessage(FORMAT_MESSAGE_ALLOCATE_BUFFER |
295 FORMAT_MESSAGE_FROM_SYSTEM |
296 FORMAT_MESSAGE_IGNORE_INSERTS, NULL, err,
297 MAKELANGID(LANG_NEUTRAL, SUBLANG_DEFAULT),
298 (LPTSTR) & lpMsgBuf, 0, NULL);
299 /*debug(("Error %ld: %s (h=%lx)\n", err, lpMsgBuf, h)); */
300 /* Free the buffer. */
308 /* If we got an address info use that... */
310 typedef int (CALLBACK * FGETNAMEINFO)
311 (const struct sockaddr FAR * sa, socklen_t salen,
312 char FAR * host, size_t hostlen, char FAR * serv,
313 size_t servlen, int flags);
314 FGETNAMEINFO fGetNameInfo = NULL;
316 /* Are we in IPv4 fallback mode? */
317 /* We put the IPv4 address into the a variable so we can further-on use the IPv4 code... */
318 if (ret->family == AF_INET)
320 (char *) &((SOCKADDR_IN *) ret->ai->
321 ai_addr)->sin_addr, sizeof(a));
323 /* Now let's find that canonicalname... */
326 (FGETNAMEINFO) GetProcAddress(dllWSHIP6,
329 ((struct sockaddr *) ret->ai->ai_addr,
331 AF_INET ? sizeof(SOCKADDR_IN) :
332 sizeof(SOCKADDR_IN6), realhost,
333 sizeof(realhost), NULL, 0, 0) != 0) {
334 strncpy(realhost, host, sizeof(realhost));
338 /* We used the IPv4-only gethostbyname()... */
342 memcpy(&a, h->h_addr, sizeof(a));
343 /* This way we are always sure the h->h_name is valid :) */
344 strncpy(realhost, h->h_name, sizeof(realhost));
348 FreeLibrary(dllWSHIP6);
352 * This must be a numeric IPv4 address because it caused a
353 * success return from inet_addr.
355 ret->family = AF_INET;
356 strncpy(realhost, host, sizeof(realhost));
358 ret->address = ntohl(a);
359 realhost[lenof(realhost)-1] = '\0';
360 *canonicalname = smalloc(1+strlen(realhost));
361 strcpy(*canonicalname, realhost);
365 SockAddr sk_nonamelookup(char *host)
367 SockAddr ret = smalloc(sizeof(struct SockAddr_tag));
368 ret->family = AF_UNSPEC;
369 strncpy(ret->hostname, host, lenof(ret->hostname));
370 ret->hostname[lenof(ret->hostname)-1] = '\0';
374 void sk_getaddr(SockAddr addr, char *buf, int buflen)
377 if (addr->family == AF_INET6) {
378 FIXME; /* I don't know how to get a text form of an IPv6 address. */
381 if (addr->family == AF_INET) {
383 a.s_addr = htonl(addr->address);
384 strncpy(buf, inet_ntoa(a), buflen);
385 buf[buflen-1] = '\0';
387 assert(addr->family == AF_UNSPEC);
388 strncpy(buf, addr->hostname, buflen);
389 buf[buflen-1] = '\0';
393 int sk_hostname_is_local(char *name)
395 return !strcmp(name, "localhost");
398 int sk_address_is_local(SockAddr addr)
401 if (addr->family == AF_INET6) {
402 FIXME; /* someone who can compile for IPV6 had better do this bit */
405 if (addr->family == AF_INET) {
407 a.s_addr = htonl(addr->address);
408 return ipv4_is_loopback(a);
410 assert(addr->family == AF_UNSPEC);
411 return 0; /* we don't know; assume not */
415 int sk_addrtype(SockAddr addr)
417 return (addr->family == AF_INET ? ADDRTYPE_IPV4 :
419 addr->family == AF_INET6 ? ADDRTYPE_IPV6 :
424 void sk_addrcopy(SockAddr addr, char *buf)
426 assert(addr->family != AF_UNSPEC);
428 if (addr->family == AF_INET6) {
429 memcpy(buf, (char*) addr->ai, 16);
432 if (addr->family == AF_INET) {
434 a.s_addr = htonl(addr->address);
435 memcpy(buf, (char*) &a.s_addr, 4);
439 void sk_addr_free(SockAddr addr)
444 static Plug sk_tcp_plug(Socket sock, Plug p)
446 Actual_Socket s = (Actual_Socket) sock;
453 static void sk_tcp_flush(Socket s)
456 * We send data to the socket as soon as we can anyway,
457 * so we don't need to do anything here. :-)
461 static void sk_tcp_close(Socket s);
462 static int sk_tcp_write(Socket s, char *data, int len);
463 static int sk_tcp_write_oob(Socket s, char *data, int len);
464 static void sk_tcp_set_private_ptr(Socket s, void *ptr);
465 static void *sk_tcp_get_private_ptr(Socket s);
466 static void sk_tcp_set_frozen(Socket s, int is_frozen);
467 static char *sk_tcp_socket_error(Socket s);
469 extern char *do_select(SOCKET skt, int startup);
471 Socket sk_register(void *sock, Plug plug)
473 static struct socket_function_table fn_table = {
479 sk_tcp_set_private_ptr,
480 sk_tcp_get_private_ptr,
490 * Create Socket structure.
492 ret = smalloc(sizeof(struct Socket_tag));
496 bufchain_init(&ret->output_data);
497 ret->writable = 1; /* to start with */
498 ret->sending_oob = 0;
500 ret->frozen_readable = 0;
501 ret->localhost_only = 0; /* unused, but best init anyway */
502 ret->pending_error = 0;
504 ret->s = (SOCKET)sock;
506 if (ret->s == INVALID_SOCKET) {
507 err = WSAGetLastError();
508 ret->error = winsock_error_string(err);
514 /* Set up a select mechanism. This could be an AsyncSelect on a
515 * window, or an EventSelect on an event object. */
516 errstr = do_select(ret->s, 1);
527 Socket sk_new(SockAddr addr, int port, int privport, int oobinline,
528 int nodelay, Plug plug)
530 static struct socket_function_table fn_table = {
536 sk_tcp_set_private_ptr,
537 sk_tcp_get_private_ptr,
553 * Create Socket structure.
555 ret = smalloc(sizeof(struct Socket_tag));
559 bufchain_init(&ret->output_data);
560 ret->connected = 0; /* to start with */
561 ret->writable = 0; /* to start with */
562 ret->sending_oob = 0;
564 ret->frozen_readable = 0;
565 ret->localhost_only = 0; /* unused, but best init anyway */
566 ret->pending_error = 0;
571 assert(addr->family != AF_UNSPEC);
572 s = socket(addr->family, SOCK_STREAM, 0);
575 if (s == INVALID_SOCKET) {
576 err = WSAGetLastError();
577 ret->error = winsock_error_string(err);
581 ret->oobinline = oobinline;
584 setsockopt(s, SOL_SOCKET, SO_OOBINLINE, (void *) &b, sizeof(b));
589 setsockopt(s, IPPROTO_TCP, TCP_NODELAY, (void *) &b, sizeof(b));
593 * Bind to local address.
596 localport = 1023; /* count from 1023 downwards */
598 localport = 0; /* just use port 0 (ie winsock picks) */
600 /* Loop round trying to bind */
605 if (addr->family == AF_INET6) {
606 memset(&a6, 0, sizeof(a6));
607 a6.sin6_family = AF_INET6;
608 /*a6.sin6_addr = in6addr_any; *//* == 0 */
609 a6.sin6_port = htons(localport);
613 a.sin_family = AF_INET;
614 a.sin_addr.s_addr = htonl(INADDR_ANY);
615 a.sin_port = htons(localport);
618 retcode = bind(s, (addr->family == AF_INET6 ?
619 (struct sockaddr *) &a6 :
620 (struct sockaddr *) &a),
622 AF_INET6 ? sizeof(a6) : sizeof(a)));
624 retcode = bind(s, (struct sockaddr *) &a, sizeof(a));
626 if (retcode != SOCKET_ERROR) {
630 err = WSAGetLastError();
631 if (err != WSAEADDRINUSE) /* failed, for a bad reason */
636 break; /* we're only looping once */
639 break; /* we might have got to the end */
643 ret->error = winsock_error_string(err);
648 * Connect to remote address.
651 if (addr->family == AF_INET6) {
652 memset(&a, 0, sizeof(a));
653 a6.sin6_family = AF_INET6;
654 a6.sin6_port = htons((short) port);
656 ((struct sockaddr_in6 *) addr->ai->ai_addr)->sin6_addr;
660 a.sin_family = AF_INET;
661 a.sin_addr.s_addr = htonl(addr->address);
662 a.sin_port = htons((short) port);
665 /* Set up a select mechanism. This could be an AsyncSelect on a
666 * window, or an EventSelect on an event object. */
667 errstr = do_select(s, 1);
675 connect(s, ((addr->family == AF_INET6) ?
676 (struct sockaddr *) &a6 : (struct sockaddr *) &a),
677 (addr->family == AF_INET6) ? sizeof(a6) : sizeof(a))
679 connect(s, (struct sockaddr *) &a, sizeof(a))
682 err = WSAGetLastError();
684 * We expect a potential EWOULDBLOCK here, because the
685 * chances are the front end has done a select for
686 * FD_CONNECT, so that connect() will complete
689 if ( err != WSAEWOULDBLOCK ) {
690 ret->error = winsock_error_string(err);
695 * If we _don't_ get EWOULDBLOCK, the connect has completed
696 * and we should set the socket as writable.
706 Socket sk_newlistener(char *srcaddr, int port, Plug plug, int local_host_only)
708 static struct socket_function_table fn_table = {
714 sk_tcp_set_private_ptr,
715 sk_tcp_get_private_ptr,
732 * Create Socket structure.
734 ret = smalloc(sizeof(struct Socket_tag));
738 bufchain_init(&ret->output_data);
739 ret->writable = 0; /* to start with */
740 ret->sending_oob = 0;
742 ret->frozen_readable = 0;
743 ret->localhost_only = local_host_only;
744 ret->pending_error = 0;
749 s = socket(AF_INET, SOCK_STREAM, 0);
752 if (s == INVALID_SOCKET) {
753 err = WSAGetLastError();
754 ret->error = winsock_error_string(err);
760 setsockopt(s, SOL_SOCKET, SO_REUSEADDR, (const char *)&on, sizeof(on));
763 if (addr->family == AF_INET6) {
764 memset(&a6, 0, sizeof(a6));
765 a6.sin6_family = AF_INET6;
766 /* FIXME: srcaddr is ignored for IPv6, because I (SGT) don't
767 * know how to do it. :-) */
769 a6.sin6_addr = in6addr_loopback;
771 a6.sin6_addr = in6addr_any;
772 a6.sin6_port = htons(port);
777 a.sin_family = AF_INET;
780 * Bind to source address. First try an explicitly
784 a.sin_addr.s_addr = inet_addr(srcaddr);
785 if (a.sin_addr.s_addr != INADDR_NONE) {
786 /* Override localhost_only with specified listen addr. */
787 ret->localhost_only = ipv4_is_loopback(a.sin_addr);
793 * ... and failing that, go with one of the standard ones.
797 a.sin_addr.s_addr = htonl(INADDR_LOOPBACK);
799 a.sin_addr.s_addr = htonl(INADDR_ANY);
802 a.sin_port = htons((short)port);
805 retcode = bind(s, (addr->family == AF_INET6 ?
806 (struct sockaddr *) &a6 :
807 (struct sockaddr *) &a),
809 AF_INET6 ? sizeof(a6) : sizeof(a)));
811 retcode = bind(s, (struct sockaddr *) &a, sizeof(a));
813 if (retcode != SOCKET_ERROR) {
816 err = WSAGetLastError();
820 ret->error = winsock_error_string(err);
825 if (listen(s, SOMAXCONN) == SOCKET_ERROR) {
827 ret->error = winsock_error_string(err);
831 /* Set up a select mechanism. This could be an AsyncSelect on a
832 * window, or an EventSelect on an event object. */
833 errstr = do_select(s, 1);
844 static void sk_tcp_close(Socket sock)
846 extern char *do_select(SOCKET skt, int startup);
847 Actual_Socket s = (Actual_Socket) sock;
856 * The function which tries to send on a socket once it's deemed
859 void try_send(Actual_Socket s)
861 while (s->sending_oob || bufchain_size(&s->output_data) > 0) {
867 if (s->sending_oob) {
868 urgentflag = MSG_OOB;
869 len = s->sending_oob;
873 bufchain_prefix(&s->output_data, &data, &len);
875 nsent = send(s->s, data, len, urgentflag);
876 noise_ultralight(nsent);
878 err = (nsent < 0 ? WSAGetLastError() : 0);
879 if ((err < WSABASEERR && nsent < 0) || err == WSAEWOULDBLOCK) {
881 * Perfectly normal: we've sent all we can for the moment.
883 * (Some WinSock send() implementations can return
884 * <0 but leave no sensible error indication -
885 * WSAGetLastError() is called but returns zero or
886 * a small number - so we check that case and treat
887 * it just like WSAEWOULDBLOCK.)
891 } else if (nsent == 0 ||
892 err == WSAECONNABORTED || err == WSAECONNRESET) {
894 * If send() returns CONNABORTED or CONNRESET, we
895 * unfortunately can't just call plug_closing(),
896 * because it's quite likely that we're currently
897 * _in_ a call from the code we'd be calling back
898 * to, so we'd have to make half the SSH code
899 * reentrant. Instead we flag a pending error on
900 * the socket, to be dealt with (by calling
901 * plug_closing()) at some suitable future moment.
903 s->pending_error = err;
906 /* We're inside the Windows frontend here, so we know
907 * that the frontend handle is unnecessary. */
908 logevent(NULL, winsock_error_string(err));
909 fatalbox("%s", winsock_error_string(err));
912 if (s->sending_oob) {
914 memmove(s->oobdata, s->oobdata+nsent, len-nsent);
915 s->sending_oob = len - nsent;
920 bufchain_consume(&s->output_data, nsent);
926 static int sk_tcp_write(Socket sock, char *buf, int len)
928 Actual_Socket s = (Actual_Socket) sock;
931 * Add the data to the buffer list on the socket.
933 bufchain_add(&s->output_data, buf, len);
936 * Now try sending from the start of the buffer list.
941 return bufchain_size(&s->output_data);
944 static int sk_tcp_write_oob(Socket sock, char *buf, int len)
946 Actual_Socket s = (Actual_Socket) sock;
949 * Replace the buffer list on the socket with the data.
951 bufchain_clear(&s->output_data);
952 assert(len <= sizeof(s->oobdata));
953 memcpy(s->oobdata, buf, len);
954 s->sending_oob = len;
957 * Now try sending from the start of the buffer list.
962 return s->sending_oob;
965 int select_result(WPARAM wParam, LPARAM lParam)
969 char buf[20480]; /* nice big buffer for plenty of speed */
973 /* wParam is the socket itself */
976 * One user has reported an assertion failure in tree234 which
977 * indicates a null element pointer has been passed to a
978 * find*234 function. The following find234 is the only one in
979 * the whole program that I can see being capable of doing
980 * this, hence I'm forced to conclude that WinSock is capable
981 * of sending me netevent messages with wParam==0. I want to
982 * know what the rest of the message is if it does so!
986 str = dupprintf("Strange WinSock message: wp=%08x lp=%08x",
987 (int)wParam, (int)lParam);
989 connection_fatal(NULL, str);
993 s = find234(sktree, (void *) wParam, cmpforsearch);
995 return 1; /* boggle */
997 if ((err = WSAGETSELECTERROR(lParam)) != 0) {
999 * An error has occurred on this socket. Pass it to the
1002 return plug_closing(s->plug, winsock_error_string(err), err, 0);
1005 noise_ultralight(lParam);
1007 switch (WSAGETSELECTEVENT(lParam)) {
1009 s->connected = s->writable = 1;
1012 /* In the case the socket is still frozen, we don't even bother */
1014 s->frozen_readable = 1;
1019 * We have received data on the socket. For an oobinline
1020 * socket, this might be data _before_ an urgent pointer,
1021 * in which case we send it to the back end with type==1
1022 * (data prior to urgent).
1026 ioctlsocket(s->s, SIOCATMARK, &atmark);
1028 * Avoid checking the return value from ioctlsocket(),
1029 * on the grounds that some WinSock wrappers don't
1030 * support it. If it does nothing, we get atmark==1,
1031 * which is equivalent to `no OOB pending', so the
1032 * effect will be to non-OOB-ify any OOB data.
1037 ret = recv(s->s, buf, sizeof(buf), 0);
1038 noise_ultralight(ret);
1040 err = WSAGetLastError();
1041 if (err == WSAEWOULDBLOCK) {
1046 return plug_closing(s->plug, winsock_error_string(err), err,
1048 } else if (0 == ret) {
1049 return plug_closing(s->plug, NULL, 0, 0);
1051 return plug_receive(s->plug, atmark ? 0 : 1, buf, ret);
1056 * This will only happen on a non-oobinline socket. It
1057 * indicates that we can immediately perform an OOB read
1058 * and get back OOB data, which we will send to the back
1059 * end with type==2 (urgent data).
1061 ret = recv(s->s, buf, sizeof(buf), MSG_OOB);
1062 noise_ultralight(ret);
1064 char *str = (ret == 0 ? "Internal networking trouble" :
1065 winsock_error_string(WSAGetLastError()));
1066 /* We're inside the Windows frontend here, so we know
1067 * that the frontend handle is unnecessary. */
1068 logevent(NULL, str);
1069 fatalbox("%s", str);
1071 return plug_receive(s->plug, 2, buf, ret);
1076 int bufsize_before, bufsize_after;
1078 bufsize_before = s->sending_oob + bufchain_size(&s->output_data);
1080 bufsize_after = s->sending_oob + bufchain_size(&s->output_data);
1081 if (bufsize_after < bufsize_before)
1082 plug_sent(s->plug, bufsize_after);
1086 /* Signal a close on the socket. First read any outstanding data. */
1089 ret = recv(s->s, buf, sizeof(buf), 0);
1091 err = WSAGetLastError();
1092 if (err == WSAEWOULDBLOCK)
1094 return plug_closing(s->plug, winsock_error_string(err),
1098 open &= plug_receive(s->plug, 0, buf, ret);
1100 open &= plug_closing(s->plug, NULL, 0, 0);
1106 struct sockaddr_in isa;
1107 int addrlen = sizeof(struct sockaddr_in);
1108 SOCKET t; /* socket of connection */
1110 memset(&isa, 0, sizeof(struct sockaddr_in));
1112 t = accept(s->s,(struct sockaddr *)&isa,&addrlen);
1113 if (t == INVALID_SOCKET)
1115 err = WSAGetLastError();
1116 if (err == WSATRY_AGAIN)
1120 if (s->localhost_only && !ipv4_is_loopback(isa.sin_addr)) {
1121 closesocket(t); /* dodgy WinSock let nonlocal through */
1122 } else if (plug_accepting(s->plug, (void*)t)) {
1123 closesocket(t); /* denied or error */
1132 * Deal with socket errors detected in try_send().
1134 void net_pending_errors(void)
1140 * This might be a fiddly business, because it's just possible
1141 * that handling a pending error on one socket might cause
1142 * others to be closed. (I can't think of any reason this might
1143 * happen in current SSH implementation, but to maintain
1144 * generality of this network layer I'll assume the worst.)
1146 * So what we'll do is search the socket list for _one_ socket
1147 * with a pending error, and then handle it, and then search
1148 * the list again _from the beginning_. Repeat until we make a
1149 * pass with no socket errors present. That way we are
1150 * protected against the socket list changing under our feet.
1154 for (i = 0; (s = index234(sktree, i)) != NULL; i++) {
1155 if (s->pending_error) {
1157 * An error has occurred on this socket. Pass it to the
1160 plug_closing(s->plug,
1161 winsock_error_string(s->pending_error),
1162 s->pending_error, 0);
1170 * Each socket abstraction contains a `void *' private field in
1171 * which the client can keep state.
1173 static void sk_tcp_set_private_ptr(Socket sock, void *ptr)
1175 Actual_Socket s = (Actual_Socket) sock;
1176 s->private_ptr = ptr;
1179 static void *sk_tcp_get_private_ptr(Socket sock)
1181 Actual_Socket s = (Actual_Socket) sock;
1182 return s->private_ptr;
1186 * Special error values are returned from sk_namelookup and sk_new
1187 * if there's a problem. These functions extract an error message,
1188 * or return NULL if there's no problem.
1190 char *sk_addr_error(SockAddr addr)
1194 static char *sk_tcp_socket_error(Socket sock)
1196 Actual_Socket s = (Actual_Socket) sock;
1200 static void sk_tcp_set_frozen(Socket sock, int is_frozen)
1202 Actual_Socket s = (Actual_Socket) sock;
1203 if (s->frozen == is_frozen)
1205 s->frozen = is_frozen;
1206 if (!is_frozen && s->frozen_readable) {
1208 recv(s->s, &c, 1, MSG_PEEK);
1210 s->frozen_readable = 0;
1214 * For Plink: enumerate all sockets currently active.
1216 SOCKET first_socket(int *state)
1220 s = index234(sktree, (*state)++);
1221 return s ? s->s : INVALID_SOCKET;
1224 SOCKET next_socket(int *state)
1226 Actual_Socket s = index234(sktree, (*state)++);
1227 return s ? s->s : INVALID_SOCKET;
1230 int net_service_lookup(char *service)
1233 se = getservbyname(service, NULL);
1235 return ntohs(se->s_port);