2f75bae1 |
1 | /* |
2 | * Windows networking abstraction. |
3 | */ |
4 | |
5 | #include <windows.h> |
6 | #include <winsock.h> |
7 | #include <stdio.h> |
8 | |
9 | #include "putty.h" |
10 | #include "network.h" |
11 | #include "tree234.h" |
12 | |
13 | #define BUFFER_GRANULE 512 |
14 | |
15 | struct Socket_tag { |
16 | char *error; |
17 | SOCKET s; |
18 | sk_receiver_t receiver; |
19 | void *private_ptr; |
20 | struct buffer *head, *tail; |
21 | int writable; |
22 | int in_oob, sending_oob; |
23 | }; |
24 | |
25 | struct SockAddr_tag { |
26 | char *error; |
27 | unsigned long address; |
28 | }; |
29 | |
30 | struct buffer { |
31 | struct buffer *next; |
32 | int buflen, bufpos; |
33 | char buf[BUFFER_GRANULE]; |
34 | }; |
35 | |
36 | static tree234 *sktree; |
37 | |
38 | static int cmpfortree(void *av, void *bv) { |
39 | Socket a = (Socket)av, b = (Socket)bv; |
40 | unsigned long as = (unsigned long)a->s, bs = (unsigned long)b->s; |
41 | if (as < bs) return -1; |
42 | if (as > bs) return +1; |
43 | return 0; |
44 | } |
45 | |
46 | static int cmpforsearch(void *av, void *bv) { |
47 | Socket b = (Socket)bv; |
48 | unsigned long as = (unsigned long)av, bs = (unsigned long)b->s; |
49 | if (as < bs) return -1; |
50 | if (as > bs) return +1; |
51 | return 0; |
52 | } |
53 | |
54 | void sk_init(void) { |
55 | sktree = newtree234(cmpfortree); |
56 | } |
57 | |
58 | SockAddr sk_namelookup(char *host, char **canonicalname) { |
59 | SockAddr ret = smalloc(sizeof(struct SockAddr_tag)); |
60 | unsigned long a; |
61 | struct hostent *h; |
62 | |
63 | if ( (a = inet_addr(host)) == (unsigned long) INADDR_NONE) { |
64 | if ( (h = gethostbyname(host)) == NULL) { |
65 | DWORD err = WSAGetLastError(); |
66 | ret->error = (err == WSAENETDOWN ? "Network is down" : |
67 | err == WSAHOST_NOT_FOUND ? "Host does not exist" : |
68 | err == WSATRY_AGAIN ? "Host not found" : |
69 | "gethostbyname: unknown error"); |
70 | } else { |
71 | ret->error = NULL; |
72 | memcpy (&a, h->h_addr, sizeof(a)); |
73 | *canonicalname = h->h_name; |
74 | } |
75 | } else { |
76 | *canonicalname = host; |
77 | } |
78 | ret->address = ntohl(a); |
79 | |
80 | return ret; |
81 | } |
82 | |
83 | void sk_addr_free(SockAddr addr) { |
84 | sfree(addr); |
85 | } |
86 | |
87 | Socket sk_new(SockAddr addr, int port, sk_receiver_t receiver) { |
88 | SOCKET s; |
89 | SOCKADDR_IN a; |
90 | DWORD err; |
91 | char *errstr; |
92 | Socket ret; |
93 | extern char *do_select(SOCKET skt, int startup); |
94 | |
95 | /* |
96 | * Create Socket structure. |
97 | */ |
98 | ret = smalloc(sizeof(struct Socket_tag)); |
99 | ret->error = NULL; |
100 | ret->receiver = receiver; |
101 | ret->head = ret->tail = NULL; |
102 | ret->writable = 1; /* to start with */ |
103 | ret->in_oob = FALSE; |
33232c8f |
104 | ret->sending_oob = 0; |
2f75bae1 |
105 | |
106 | /* |
107 | * Open socket. |
108 | */ |
109 | s = socket(AF_INET, SOCK_STREAM, 0); |
110 | ret->s = s; |
111 | |
112 | if (s == INVALID_SOCKET) { |
113 | err = WSAGetLastError(); |
114 | ret->error = (err == WSAENETDOWN ? "Network is down" : |
115 | err == WSAEAFNOSUPPORT ? "TCP/IP support not present" : |
116 | "socket(): unknown error"); |
117 | return ret; |
118 | } |
119 | |
120 | /* |
121 | * Bind to local address. |
122 | */ |
123 | a.sin_family = AF_INET; |
124 | a.sin_addr.s_addr = htonl(INADDR_ANY); |
125 | a.sin_port = htons(0); |
126 | if (bind (s, (struct sockaddr *)&a, sizeof(a)) == SOCKET_ERROR) { |
127 | err = WSAGetLastError(); |
128 | ret->error = (err == WSAENETDOWN ? "Network is down" : |
129 | "bind(): unknown error"); |
130 | return ret; |
131 | } |
132 | |
133 | /* |
134 | * Connect to remote address. |
135 | */ |
136 | a.sin_addr.s_addr = htonl(addr->address); |
137 | a.sin_port = htons((short)port); |
138 | if (connect (s, (struct sockaddr *)&a, sizeof(a)) == SOCKET_ERROR) { |
139 | err = WSAGetLastError(); |
140 | ret->error = (err == WSAENETDOWN ? "Network is down" : |
141 | err == WSAECONNREFUSED ? "Connection refused" : |
142 | err == WSAENETUNREACH ? "Network is unreachable" : |
143 | err == WSAEHOSTUNREACH ? "No route to host" : |
144 | "connect(): unknown error"); |
145 | return ret; |
146 | } |
147 | |
148 | /* Set up a select mechanism. This could be an AsyncSelect on a |
149 | * window, or an EventSelect on an event object. */ |
150 | errstr = do_select(s, 1); |
151 | if (errstr) { |
152 | ret->error = errstr; |
153 | return ret; |
154 | } |
155 | |
156 | add234(sktree, ret); |
157 | |
158 | return ret; |
159 | } |
160 | |
161 | void sk_close(Socket s) { |
162 | del234(sktree, s); |
163 | do_select(s->s, 0); |
164 | closesocket(s->s); |
165 | free(s); |
166 | } |
167 | |
168 | char *winsock_error_string(int error) { |
169 | switch (error) { |
170 | case WSAEACCES: return "Network error: Permission denied"; |
171 | case WSAEADDRINUSE: return "Network error: Address already in use"; |
172 | case WSAEADDRNOTAVAIL: return "Network error: Cannot assign requested address"; |
173 | case WSAEAFNOSUPPORT: return "Network error: Address family not supported by protocol family"; |
174 | case WSAEALREADY: return "Network error: Operation already in progress"; |
175 | case WSAECONNABORTED: return "Network error: Software caused connection abort"; |
176 | case WSAECONNREFUSED: return "Network error: Connection refused"; |
177 | case WSAECONNRESET: return "Network error: Connection reset by peer"; |
178 | case WSAEDESTADDRREQ: return "Network error: Destination address required"; |
179 | case WSAEFAULT: return "Network error: Bad address"; |
180 | case WSAEHOSTDOWN: return "Network error: Host is down"; |
181 | case WSAEHOSTUNREACH: return "Network error: No route to host"; |
182 | case WSAEINPROGRESS: return "Network error: Operation now in progress"; |
183 | case WSAEINTR: return "Network error: Interrupted function call"; |
184 | case WSAEINVAL: return "Network error: Invalid argument"; |
185 | case WSAEISCONN: return "Network error: Socket is already connected"; |
186 | case WSAEMFILE: return "Network error: Too many open files"; |
187 | case WSAEMSGSIZE: return "Network error: Message too long"; |
188 | case WSAENETDOWN: return "Network error: Network is down"; |
189 | case WSAENETRESET: return "Network error: Network dropped connection on reset"; |
190 | case WSAENETUNREACH: return "Network error: Network is unreachable"; |
191 | case WSAENOBUFS: return "Network error: No buffer space available"; |
192 | case WSAENOPROTOOPT: return "Network error: Bad protocol option"; |
193 | case WSAENOTCONN: return "Network error: Socket is not connected"; |
194 | case WSAENOTSOCK: return "Network error: Socket operation on non-socket"; |
195 | case WSAEOPNOTSUPP: return "Network error: Operation not supported"; |
196 | case WSAEPFNOSUPPORT: return "Network error: Protocol family not supported"; |
197 | case WSAEPROCLIM: return "Network error: Too many processes"; |
198 | case WSAEPROTONOSUPPORT: return "Network error: Protocol not supported"; |
199 | case WSAEPROTOTYPE: return "Network error: Protocol wrong type for socket"; |
200 | case WSAESHUTDOWN: return "Network error: Cannot send after socket shutdown"; |
201 | case WSAESOCKTNOSUPPORT: return "Network error: Socket type not supported"; |
202 | case WSAETIMEDOUT: return "Network error: Connection timed out"; |
203 | case WSAEWOULDBLOCK: return "Network error: Resource temporarily unavailable"; |
204 | case WSAEDISCON: return "Network error: Graceful shutdown in progress"; |
205 | default: return "Unknown network error"; |
206 | } |
207 | } |
208 | |
209 | /* |
210 | * The function which tries to send on a socket once it's deemed |
211 | * writable. |
212 | */ |
213 | void try_send(Socket s) { |
214 | while (s->head) { |
215 | int nsent; |
216 | DWORD err; |
217 | int len, urgentflag; |
218 | |
219 | if (s->sending_oob) { |
220 | urgentflag = MSG_OOB; |
221 | len = s->sending_oob; |
222 | } else { |
223 | urgentflag = 0; |
224 | len = s->head->buflen - s->head->bufpos; |
225 | } |
226 | |
227 | nsent = send(s->s, s->head->buf + s->head->bufpos, len, urgentflag); |
228 | if (nsent <= 0) { |
229 | err = (nsent < 0 ? WSAGetLastError() : 0); |
230 | if (err == WSAEWOULDBLOCK) { |
231 | /* Perfectly normal: we've sent all we can for the moment. */ |
232 | s->writable = FALSE; |
233 | return; |
234 | } else if (nsent == 0 || |
235 | err == WSAECONNABORTED || |
236 | err == WSAECONNRESET) { |
237 | /* |
238 | * FIXME. This will have to be done better when we |
239 | * start managing multiple sockets (e.g. SSH port |
240 | * forwarding), because if we get CONNRESET while |
241 | * trying to write a particular forwarded socket |
242 | * then it isn't necessarily the end of the world. |
243 | * Ideally I'd like to pass the error code back to |
244 | * somewhere the next select_result() will see it, |
245 | * but that might be hard. Perhaps I should pass it |
246 | * back to be queued in the Windows front end bit. |
247 | */ |
248 | fatalbox(winsock_error_string(err)); |
249 | } else { |
250 | fatalbox(winsock_error_string(err)); |
251 | } |
252 | } else { |
253 | s->head->bufpos += nsent; |
254 | if (s->sending_oob) |
255 | s->sending_oob -= nsent; |
256 | if (s->head->bufpos >= s->head->buflen) { |
257 | struct buffer *tmp = s->head; |
258 | s->head = tmp->next; |
259 | free(tmp); |
260 | if (!s->head) |
261 | s->tail = NULL; |
262 | } |
263 | } |
264 | } |
265 | } |
266 | |
267 | void sk_write(Socket s, char *buf, int len) { |
268 | /* |
269 | * Add the data to the buffer list on the socket. |
270 | */ |
271 | if (s->tail && s->tail->buflen < BUFFER_GRANULE) { |
272 | int copylen = min(len, BUFFER_GRANULE - s->tail->buflen); |
273 | memcpy(s->tail->buf + s->tail->buflen, buf, copylen); |
274 | buf += copylen; |
275 | len -= copylen; |
276 | s->tail->buflen += copylen; |
277 | } |
278 | while (len > 0) { |
279 | int grainlen = min(len, BUFFER_GRANULE); |
280 | struct buffer *newbuf; |
281 | newbuf = smalloc(sizeof(struct buffer)); |
282 | newbuf->bufpos = 0; |
283 | newbuf->buflen = grainlen; |
284 | memcpy(newbuf->buf, buf, grainlen); |
285 | buf += grainlen; |
286 | len -= grainlen; |
287 | if (s->tail) |
288 | s->tail->next = newbuf; |
289 | else |
290 | s->head = s->tail = newbuf; |
291 | newbuf->next = NULL; |
292 | s->tail = newbuf; |
293 | } |
294 | |
295 | /* |
296 | * Now try sending from the start of the buffer list. |
297 | */ |
298 | if (s->writable) |
299 | try_send(s); |
300 | } |
301 | |
302 | void sk_write_oob(Socket s, char *buf, int len) { |
303 | /* |
304 | * Replace the buffer list on the socket with the data. |
305 | */ |
306 | if (!s->head) { |
307 | s->head = smalloc(sizeof(struct buffer)); |
308 | } else { |
309 | struct buffer *walk = s->head->next; |
310 | while (walk) { |
311 | struct buffer *tmp = walk; |
312 | walk = tmp->next; |
313 | free(tmp); |
314 | } |
315 | } |
316 | s->head->next = NULL; |
317 | s->tail = s->head; |
318 | s->head->buflen = len; |
319 | memcpy(s->head->buf, buf, len); |
320 | |
321 | /* |
322 | * Set the Urgent marker. |
323 | */ |
324 | s->sending_oob = len; |
325 | |
326 | /* |
327 | * Now try sending from the start of the buffer list. |
328 | */ |
329 | if (s->writable) |
330 | try_send(s); |
331 | } |
332 | |
333 | int select_result(WPARAM wParam, LPARAM lParam) { |
334 | int ret; |
335 | DWORD err; |
336 | char buf[BUFFER_GRANULE]; |
337 | Socket s; |
338 | int atmark; |
339 | |
340 | /* wParam is the socket itself */ |
341 | s = find234(sktree, (void *)wParam, cmpforsearch); |
342 | if (!s) |
343 | return 1; /* boggle */ |
344 | |
345 | if ((err = WSAGETSELECTERROR(lParam)) != 0) { |
346 | fatalbox(winsock_error_string(err)); |
347 | } |
348 | |
349 | switch (WSAGETSELECTEVENT(lParam)) { |
350 | case FD_READ: |
351 | ret = recv(s->s, buf, sizeof(buf), 0); |
352 | if (ret < 0) { |
353 | err = WSAGetLastError(); |
354 | if (err == WSAEWOULDBLOCK) { |
355 | break; |
356 | } |
357 | } |
358 | if (ret < 0) { |
359 | fatalbox(winsock_error_string(err)); |
360 | } else { |
361 | int type = s->in_oob ? 2 : 0; |
362 | s->in_oob = FALSE; |
363 | return s->receiver(s, type, buf, ret); |
364 | } |
365 | break; |
366 | case FD_OOB: |
367 | /* |
368 | * Read all data up to the OOB marker, and send it to the |
369 | * receiver with urgent==1 (OOB pending). |
370 | */ |
371 | atmark = 1; |
372 | s->in_oob = TRUE; |
373 | /* Some WinSock wrappers don't support this call, so we |
374 | * deliberately don't check the return value. If the call |
375 | * fails and does nothing, we will get back atmark==1, |
376 | * which is good enough to keep going at least. */ |
377 | ioctlsocket(s->s, SIOCATMARK, &atmark); |
378 | ret = recv(s->s, buf, sizeof(buf), MSG_OOB); |
379 | if (ret <= 0) { |
380 | fatalbox(ret == 0 ? "Internal networking trouble" : |
381 | winsock_error_string(WSAGetLastError())); |
382 | } else { |
383 | return s->receiver(s, atmark ? 2 : 1, buf, ret); |
384 | } |
385 | break; |
386 | case FD_WRITE: |
387 | s->writable = 1; |
388 | try_send(s); |
389 | break; |
390 | case FD_CLOSE: |
391 | /* Signal a close on the socket. */ |
392 | return s->receiver(s, 0, NULL, 0); |
393 | break; |
394 | } |
395 | |
396 | return 1; |
397 | } |
398 | |
399 | /* |
400 | * Each socket abstraction contains a `void *' private field in |
401 | * which the client can keep state. |
402 | */ |
403 | void sk_set_private_ptr(Socket s, void *ptr) { |
404 | s->private_ptr = ptr; |
405 | } |
406 | void *sk_get_private_ptr(Socket s) { |
407 | return s->private_ptr; |
408 | } |
409 | |
410 | /* |
411 | * Special error values are returned from sk_namelookup and sk_new |
412 | * if there's a problem. These functions extract an error message, |
413 | * or return NULL if there's no problem. |
414 | */ |
415 | char *sk_addr_error(SockAddr addr) { |
416 | return addr->error; |
417 | } |
418 | char *sk_socket_error(Socket s) { |
419 | return s->error; |
420 | } |
421 | |
422 | /* |
423 | * For Plink: enumerate all sockets currently active. |
424 | */ |
425 | SOCKET first_socket(enum234 *e) { |
426 | Socket s = first234(sktree, e); |
427 | return s ? s->s : INVALID_SOCKET; |
428 | } |
429 | SOCKET next_socket(enum234 *e) { |
430 | Socket s = next234(e); |
431 | return s ? s->s : INVALID_SOCKET; |
432 | } |